Administering a shared, on-line pool of data storage resources for performing data storage operations

ABSTRACT

A data storage system according to certain aspects manages and administers the sharing of storage resources among clients in the shared storage pool. The shared storage pool according to certain aspects can provide readily available remote storage to clients in the pool. A share list for each client may be used to determine where data is stored within the storage pool. The share list may include clients that are known to each client, and therefore, a user may feel more at ease storing the data on the clients in the storage pool. Management and administration of the storage pool and backup and restore jobs can be performed by an entity other than the client, making backup and restore more streamlined and simple for the clients in the pool.

INCORPORATION BY REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of priority under 35 U.S.C. §119(e)of U.S. Provisional Application No. 61/677,712 filed on Jul. 31, 2012and entitled “ADMINISTERING A SHARED, ON-LINE POOL OF DATA STORAGERESOURCES FOR PERFORMING DATA STORAGE OPERATIONS”, the entirety of whichis incorporated herein by reference. Any and all priority claimsidentified in the Application Data Sheet, or any correction thereto, arehereby incorporated by reference under 37 CFR 1.57.

BACKGROUND

Businesses worldwide recognize the commercial value of their data andseek reliable, cost-effective ways to protect the information stored ontheir computer networks while minimizing impact on productivity.Protecting information is often part of a routine process that isperformed within an organization.

A company might back up critical computing systems such as databases,file servers, web servers, and so on as part of a daily, weekly, ormonthly maintenance schedule. The company may similarly protectcomputing systems used by each of its employees, such as those used byan accounting department, marketing department, engineering department,and so forth.

Given the rapidly expanding volume of data under management, companiesalso continue to seek innovative techniques for managing data growth, inaddition to protecting data. For instance, companies often implementmigration techniques for moving data to lower cost storage over time anddata reduction techniques for reducing redundant data, pruning lowerpriority data, etc.

Enterprises also increasingly view their stored data as a valuableasset. Along these lines, customers are looking for solutions that notonly protect and manage, but also leverage their data. For instance,solutions providing data analysis capabilities, improved datapresentation and access features, and the like, are in increasingdemand.

SUMMARY

In view of the above, individual users may create copies of productiondata, and access the copies for recovery purposes. Such recovery copiescan be accessed in the event their computers or devices fail orotherwise become unavailable. For instance, in some existing systems thedata may be copied to a storage device that is separate from personalcomputers or devices, such as a portable or an external hard drive orstorage available from a storage provider. However, in some cases, usersmay not have sufficient storage capacity to meet their data protectionneeds, or may not want to maintain large amounts of data storage devicesin their home or office. Moreover, even where a user purchases orotherwise has access to sufficient storage capacity, they may haveexcess storage capacity and may not be able to efficiently utilize allof the storage capacity that they have at any given time.

Due to the above challenges, there is a need for a user-friendly,efficient mechanism for individuals or other entities to meet their dataprotection needs. In order to address these and other challenges,certain storage systems disclosed herein provide a centralized storagemanager that administers a shared, on-line storage pool. For instance,each member in the storage pool uses an on-line interface to contributelocal storage resources to the wider pool. A storage pool managermanages membership to the pool and administers the pool resources. Themanager also services requests from the various users to backup data tothe pool.

Some or all of the members in the pool locally install a backup clientthat transmits requests to the storage manager to back up that user'sdata. In some cases, some or all of the users also locally install amedia agent module that conducts backup data from other users to thatuser's local storage pool devices. The storage pool manager allocatesthe storage operations amongst the resources in the pool, monitorsand/or reports the success or failure of storage operations, theavailability of particular resources in the pool, etc.

Because secondary copies of a member's data may be stored in targetmedia belonging to one or more other members, the secondary copies arestored remotely from the primary copies of the data. This providesadditional security in the event of disasters or other events in whichlocal copies of data are lost. Thus, the secondary copies can act asdisaster recovery copies. Also, the pool can include generally anynumber (e.g., tens, hundreds, thousands or millions of members) ofmembers. Thus, secondary copies or portions thereof can be allocatedamongst storage resources of many geographically diverse members,providing additional protection. In such cases, in the event that thestorage resources of any given member in the pool are compromised, onlya relatively small portion of a user's data, if any, may be lost.

The many-user, de-centralized nature of the sharing scheme can alsoprovide a high degree of flexibility. For instance, if a particularmember's storage resources are not currently or historically available,the storage manager may select other, relatively more available storageresources in the pool for a given data protection job. Also, storageresources associated with members having excess storage capacity can beutilized by other members in the pool. Moreover, members who wouldprefer not to locally maintain large amounts of storage media canutilize the storage pool to meet their storage needs. These are just afew examples of some benefits provided by the systems and methodsprovided herein.

The system facilitates efficient sharing of storage resources in a givenstorage pool amongst the resources of the various members (also referredto as clients). In the shared storage pool, secondary copies of clientdata in some embodiments are created by transferring data directlybetween two clients, e.g., through a peer-to-peer connection, ratherthan being uploaded to some third party location, for example. Forinstance, the storage manager may conduct a backup job by copying datafrom a first client to storage associated with one or more secondclients in the storage pool.

The shared storage pool according to certain aspects may operateaccording to share lists for each client. For example, where the storagemanager is tasked with backing up data for a first client in the pool,the storage manager may select one or destination storage devices in thepool only if the client(s) owning or otherwise associated with thosestorage devices appear on the share list for the first client. Thestorage manager can maintain and administer updates to the share list,and in some embodiments users in the pool update their share lists usingan interface hosted by the storage manager, such as a GUI on a webportal, for example. In some embodiments, such a share list can bederived from, utilize, or otherwise be based on the friend list fromsome third party web site or other source, such as a social networkingwebsite, such as Facebook or MSN. Data may be encrypted for privacy andsecurity purposes.

A data storage system according to certain aspects manages andadministers the sharing of storage resources among clients in the sharedstorage pool. The data storage system may include a backup module thatmanages backup and restore requests from clients in the storage pool. Inresponse to a backup request from a particular client, the backup modulemay refer to the share list for that client and send informationregarding the parameters related to backup or the storage pool. Suchparameters may include backup location(s) among others and may be basedon client configuration information. Client configuration informationmay include what type of processor and storage each client provides. Thebackup module may maintain a list of backup and restore operations andrelated status information, e.g., in the form of an index of jobs. Inresponse to restore requests, the backup module may refer to such anindex and send information regarding the parameters related to restore.Clients storing data for other clients may send backup/restore reportsto the backup module and/or the client that requested backup or restore.

In this manner, a shared storage pool can provide readily availableremote storage to clients in the pool. A share list for each client maybe used to determine where data is stored within the storage pool. Theshare list may include clients that are known to each client, andtherefore, a user may feel more at ease storing the data on the clientsin the storage pool. Management and administration of the storage pooland backup and restore jobs can be performed by an entity other than theclient, making backup and restore more streamlined and simple for theclients in the pool.

According to certain embodiments, a method is provided for administeringa shared pool of storage resources. The method comprises electronicallydistributing data protection software to a plurality of users who eachcontribute storage resources to a shared pool of storage resources. Thedata protection software is installed on at least one computing deviceof each user, and the computing devices of the plurality of users are innetworked communication with one another. The method further comprisesfor each respective user of the plurality of users, maintaining, by astorage manager executing in one or more processors, a first datastructure including an indication as to an amount of available storageresources contributed to the shared pool by the respective user, anddetermining, by the storage manager, that a copy operation is to beperformed on data stored in primary storage associated with a first userof the plurality of users. The method further comprises consulting, bythe storage manager, the first data structure to identify availablestorage resources contributed to the shared pool by a second user of theplurality of users, and instructing the data protection softwareinstalled on the computing device of the first user to initiate the copyoperation, where data involved in the copy operation is communicated toand copied into the contributed storage resources of the second user.

In some embodiments a method of creating secondary copies of dataassociated with user computing devices in a shared storage pool isprovided. The method comprises, in response to instructions to create asecondary copy of first data stored in primary storage associated with afirst computing device in a networked pool of computing devices,accessing a data structure associated with the first computing devicethat identifies a first subset of computing devices in the pool that aredesignated for sharing storage resources with the first computingdevice. The method further comprises instructing, by a storage managermodule executing in one or more processors, the first computing deviceto transmit the first data to a media agent associated with at least onecomputing device in the pool and which creates the secondary copy of thefirst data in storage resources associated with a second computingdevice in the pool that is included in the first subset. In response toinstructions to create a secondary copy of second data stored in primarystorage associated with a third computing device in the pool, the methodfurther comprises accessing a data structure associated with the thirdcomputing device that identifies a second subset of computing devices inthe pool that are designated for sharing storage resources with thethird computing device. The second subset includes the first computingdevice. The method further yet comprises instructing, by the storagemanager module, the third computing device to transmit the second datato a media agent associated with at least one computing device in thepool and which creates the secondary copy of the second data in storageresources associated with the first computing device.

According to another aspect of the disclosure, a system foradministering a shared pool of networked storage resources is provided.The system comprises one or more computer processors, and a storagemanager in networked communication with a shared pool of storageresources and executing in the one or more computer processors. Thestorage manager is configured to electronically distribute dataprotection software to a plurality of users who each contribute storageresources to the shared pool of storage resources. The data protectionsoftware is installed on at least one computing device of each user, andthe computing devices of the plurality of users are in networkedcommunication with one another. For each respective user of theplurality of users, the storage manager is further configured tomaintain a first data structure including an indication as to an amountof available storage resources contributed to the shared pool by therespective user. The storage manager is further configured to determinethat a copy operation is to be performed on data stored in primarystorage associated with a first user of the plurality of users, consultthe first data structure to identify available storage resourcescontributed to the shared pool by a second user of the plurality ofusers, and instruct the data protection software installed on thecomputing device of the first user to initiate the copy operation, wheredata involved in the copy operation is communicated to and copied intothe contributed storage resources of the second user.

According to yet another aspect of the disclosure a system for creatingsecondary copies of data associated with user computing devices in ashared storage pool is provided. The system comprises a first datastructure associated with a first computing device in a networked poolof computing devices and listing a first subset of computing devices inthe pool that are designated for sharing storage resources with thefirst computing device, where a second computing device in the poolincluded in the first subset. The system further comprises a second datastructure associated with a third computing device in the pool andlisting a second subset of computing devices in the pool that aredesignated for sharing storage resources with the third computingdevice, where the second subset includes the first computing device, oneor more processors, and a storage manager module executing in the one ormore processors. The storage manager is configured to, in response toinstructions to create a secondary copy of first data stored in primarystorage associated with the first computing device, access and reviewthe first data structure to identify the first subset of computingdevices in the pool, and instruct the first computing device to transmitthe first data to a media agent associated with at least one computingdevice in the pool which creates the secondary copy of the first data instorage resources associated with the second computing device. Thestorage manager is further configured to, in response to instructions tocreate a secondary copy of second data stored in primary storageassociated with the third computing device, access and review the seconddata structure to identify the second subset of computing devices in thepool, and instruct the third computing device to transmit the seconddata to a media agent associated with at least one computing device inthe pool which creates the secondary copy of the second data in storageresources associated with the first computing device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1A is a block diagram illustrating an exemplary informationmanagement system.

FIG. 1B is a detailed view of a primary storage device, a secondarystorage device, and some examples of primary data and secondary copydata.

FIG. 1C is a block diagram of an exemplary information management systemincluding a storage manager, one or more data agents, and one or moremedia agents.

FIG. 1D is a block diagram illustrating a scalable informationmanagement system.

FIG. 1E illustrates certain secondary copy operations according to anexemplary storage policy.

FIG. 2 is a block diagram of an example storage system configured toimplement data protection operations using a shared, on-line pool ofstorage resources, according to certain embodiments.

FIG. 3 is a data flow diagram illustrative of the interaction betweenthe various components of an example storage system configured toimplement data protection operations using a shared, on-line pool ofdata storage resources, according to certain embodiments.

FIG. 4 is a data flow diagram illustrative of the interaction betweenthe various components of an example storage system configured toimplement data protection operations using a shared, on-line pool ofdata storage resources, according to certain embodiments.

FIG. 5 illustrates example data structures that can be used toadminister a shared, on-line pool of data storage resources to createand manage secondary copies of data, according to certain embodiments.

FIG. 6 is a flow diagram illustrative of one embodiment of a routine forutilizing a shared, on-line pool of data storage resources to createsecondary copies of data.

FIG. 7 is a flow diagram illustrative of one embodiment of a routine forutilizing a shared, on-line pool of data storage resources to restoresecondary copies of data.

DETAILED DESCRIPTION

Systems and methods are described herein for implementing administrationof a shared pool of data storage resources for performing data storageoperations in a data storage system. Examples of such systems andmethods are discussed in further detail herein, e.g., with respect toFIGS. 2-7. Administration of a shared pool of data storage resources forperforming data storage operations (e.g., automated administration) mayadditionally be implemented by information management systems such asthose that will now be described with respect to FIGS. 1A-1E. And, aswill be described, the componentry for implementing the techniquesdescribed herein relating to shared pooling of data storage resourcescan be incorporated into and implemented by such systems.

Information Management System Overview

With the increasing importance of protecting and leveraging data,organizations simply cannot afford to take the risk of losing criticaldata. Moreover, runaway data growth and other modern realities makeprotecting and managing data an increasingly difficult task. There istherefore a need for efficient, powerful, and user-friendly solutionsfor protecting and managing data.

Depending on the size of the organization, there are typically many dataproduction sources which are under the purview of tens, hundreds, oreven thousands of employees or other individuals. In the past,individual employees were sometimes responsible for managing andprotecting their data. A patchwork of hardware and software pointsolutions have been applied in other cases. These solutions were oftenprovided by different vendors and had limited or no interoperability.

Certain embodiments described herein provide systems and methods capableof addressing these and other shortcomings of prior approaches byimplementing unified, organization-wide information management. FIG. 1Ashows one such information management system 100, which generallyincludes combinations of hardware and software configured to protect andmanage data and metadata generated and used by the various computingdevices in the information management system 100.

The organization which employs the information management system 100 maybe a corporation or other business entity, non-profit organization,educational institution, household, governmental agency, or the like.

Generally, the systems and associated components described herein may becompatible with and/or provide some or all of the functionality of thesystems and corresponding components described in one or more of thefollowing U.S. patents and patent application publications assigned toCommVault Systems, Inc., each of which is hereby incorporated in itsentirety by reference herein:

-   -   U.S. Pat. Pub. No. 2010-0332456, entitled “DATA OBJECT STORE AND        SERVER FOR A CLOUD STORAGE ENVIRONMENT, INCLUDING DATA        DEDUPLICATION AND DATA MANAGEMENT ACROSS MULTIPLE CLOUD STORAGE        SITES”;    -   U.S. Pat. No. 7,035,880, entitled “MODULAR BACKUP AND RETRIEVAL        SYSTEM USED IN CONJUNCTION WITH A STORAGE AREA NETWORK”;    -   U.S. Pat. No. 7,343,453, entitled “HIERARCHICAL SYSTEMS AND        METHODS FOR PROVIDING A UNIFIED VIEW OF STORAGE INFORMATION”;    -   U.S. Pat. No. 7,395,282, entitled “HIERARCHICAL BACKUP AND        RETRIEVAL SYSTEM”;    -   U.S. Pat. No. 7,246,207, entitled “SYSTEM AND METHOD FOR        DYNAMICALLY PERFORMING STORAGE OPERATIONS IN A COMPUTER        NETWORK”;    -   U.S. Pat. No. 7,747,579, entitled “METABASE FOR FACILITATING        DATA CLASSIFICATION”;    -   U.S. Pat. No. 8,229,954, entitled “MANAGING COPIES OF DATA”;    -   U.S. Pat. No. 7,617,262, entitled “SYSTEM AND METHODS FOR        MONITORING APPLICATION DATA IN A DATA REPLICATION SYSTEM”;    -   U.S. Pat. No. 7,529,782, entitled “SYSTEM AND METHODS FOR        PERFORMING A SNAPSHOT AND FOR RESTORING DATA”;    -   U.S. Pat. No. 8,230,195, entitled “SYSTEM AND METHOD FOR        PERFORMING AUXILIARY STORAGE OPERATIONS”;    -   U.S. Pat. No. 8,364,652, entitled “CONTENT-ALIGNED, BLOCK-BASED        DEDUPLICATION”;    -   U.S. Pat. Pub. No. 2006/0224846, entitled “SYSTEM AND METHOD TO        SUPPORT SINGLE INSTANCE STORAGE OPERATIONS”;    -   U.S. Pat. Pub. No. 2009/0329534, entitled “APPLICATION-AWARE AND        REMOTE SINGLE INSTANCE DATA MANAGEMENT”;    -   U.S. Pat. Pub. No. 2012/0150826, entitled “DISTRIBUTED        DEDUPLICATED STORAGE SYSTEM”;    -   U.S. Pat. Pub. No. 2012/0150818, entitled “CLIENT-SIDE        REPOSITORY IN A NETWORKED DEDUPLICATED STORAGE SYSTEM”;    -   U.S. Pat. No. 8,170,995, entitled “METHOD AND SYSTEM FOR OFFLINE        INDEXING OF CONTENT AND CLASSIFYING STORED DATA”; and    -   U.S. Pat. No. 8,156,086, entitled “SYSTEMS AND METHODS FOR        STORED DATA VERIFICATION”.

The illustrated information management system 100 includes one or moreclient computing device 102 having at least one application 110executing thereon, and one or more primary storage devices 104 storingprimary data 112. The client computing device(s) 102 and the primarystorage devices 104 may generally be referred to in some cases as aprimary storage subsystem 117.

Depending on the context, the term “information management system” canrefer to generally all of the illustrated hardware and softwarecomponents. Or, in other instances, the term may refer to only a subsetof the illustrated components.

For instance, in some cases information management system 100 generallyrefers to a combination of specialized components used to protect, move,manage, manipulate and/or process data and metadata generated by theclient computing devices 102. However, the term may generally not referto the underlying components that generate and/or store the primary data112, such as the client computing devices 102 themselves, theapplications 110 and operating system residing on the client computingdevices 102, and the primary storage devices 104.

As an example, “information management system” may sometimes refer onlyto one or more of the following components and corresponding datastructures: storage managers, data agents, and media agents. Thesecomponents will be described in further detail below.

Client Computing Devices

There are typically a variety of sources in an organization that producedata to be protected and managed. As just one illustrative example, in acorporate environment such data sources can be employee workstations andcompany servers such as a mail server, a web server, or the like. In theinformation management system 100, the data generation sources includethe one or more client computing devices 102.

The client computing devices 102 may include, without limitation, one ormore: workstations, personal computers, desktop computers, or othertypes of generally fixed computing systems such as mainframe computersand minicomputers.

The client computing devices 102 can also include mobile or portablecomputing devices, such as one or more laptops, tablet computers,personal data assistants, mobile phones (such as smartphones), and othermobile or portable computing devices such as embedded computers, set topboxes, vehicle-mounted devices, wearable computers, etc.

In some cases, each client computing device 102 is associated with oneor more users and/or corresponding user accounts, of employees or otherindividuals.

The term “client computing device” is used herein because theinformation management system 100 generally “serves” the data managementand protection needs for the data generated by the client computingdevices 102. However, the use of this term does not imply that theclient computing devices 102 cannot be “servers” in other respects. Forinstance, a particular client computing device 102 may act as a serverwith respect to other devices, such as other client computing devices102. As just a few examples, the client computing devices 102 caninclude mail servers, file servers, database servers, and web servers.

The client computing devices 102 may additionally include virtualizedand/or cloud computing resources. For instance, one or more virtualmachines may be provided to the organization by a third-party cloudservice vendor. Or, in some embodiments, the client computing devices102 include one or more virtual machine(s) running on a virtual machinehost computing device operated by the organization. As one example, theorganization may use one virtual machine as a database server andanother virtual machine as a mail server. A virtual machine manager(VMM) (e.g., a Hypervisor) may manage the virtual machines, and resideand execute on the virtual machine host computing device.

Each client computing device 102 may have one or more applications 110(e.g., software applications) executing thereon which generate andmanipulate the data that is to be protected from loss.

The applications 110 generally facilitate the operations of anorganization (or multiple affiliated organizations), and can include,without limitation, mail server applications (e.g., Microsoft ExchangeServer), file server applications, mail client applications (e.g.,Microsoft Exchange Client), database applications (e.g., SQL, Oracle,SAP, Lotus Notes Database), word processing applications (e.g.,Microsoft Word), spreadsheet applications, financial applications,presentation applications, browser applications, mobile applications,entertainment applications, and so on.

The applications 110 can include at least one operating system (e.g.,Microsoft Windows, Mac OS X, iOS, IBM z/OS, Linux, other Unix-basedoperating systems, etc.), which may support one or more file systems andhost the other applications 110.

As shown, the client computing devices 102 and other components in theinformation management system 100 can be connected to one another viaone or more communication pathways 114. The communication pathways 114can include one or more networks or other connection types including asany of following, without limitation: the Internet, a wide area network(WAN), a local area network (LAN), a Storage Area Network (SAN), a FibreChannel connection, a Small Computer System Interface (SCSI) connection,a virtual private network (VPN), a token ring or TCP/IP based network,an intranet network, a point-to-point link, a cellular network, awireless data transmission system, a two-way cable system, aninteractive kiosk network, a satellite network, a broadband network, abaseband network, other appropriate wired, wireless, or partiallywired/wireless computer or telecommunications networks, combinations ofthe same or the like. The communication pathways 114 in some cases mayalso include application programming interfaces (APIs) including, e.g.,cloud service provider APIs, virtual machine management APIs, and hostedservice provider APIs.

Primary Data and Exemplary Primary Storage Devices

Primary data 112 according to some embodiments is production data orother “live” data generated by the operating system and otherapplications 110 residing on a client computing device 102. The primarydata 112 is stored on the primary storage device(s) 104 and is organizedvia a file system supported by the client computing device 102. Forinstance, the client computing device(s) 102 and correspondingapplications 110 may create, access, modify, write, delete, andotherwise use primary data 112.

Primary data 112 is generally in the native format of the sourceapplication 110. According to certain aspects, primary data 112 is aninitial or first (e.g., created before any other copies or before atleast one other copy) stored copy of data generated by the sourceapplication 110. Primary data 112 in some cases is created substantiallydirectly from data generated by the corresponding source applications110.

The primary data 112 may sometimes be referred to as a “primary copy” inthe sense that it is a discrete set of data. However, the use of thisterm does not necessarily imply that the “primary copy” is a copy in thesense that it was copied or otherwise derived from another storedversion.

The primary storage devices 104 storing the primary data 112 may berelatively fast and/or expensive (e.g., a disk drive, a hard-disk array,solid state memory, etc.). In addition, primary data 112 may be intendedfor relatively short term retention (e.g., several hours, days, orweeks).

According to some embodiments, the client computing device 102 canaccess primary data 112 from the primary storage device 104 by makingconventional file system calls via the operating system. Primary data112 representing files may include structured data (e.g., databasefiles), unstructured data (e.g., documents), and/or semi-structureddata. Some specific examples are described below with respect to FIG.1B.

It can be useful in performing certain tasks to break the primary data112 up into units of different granularities. In general, primary data112 can include files, directories, file system volumes, data blocks,extents, or any other types or granularities of data objects. As usedherein, a “data object” can refer to both (1) any file that is currentlyaddressable by a file system or that was previously addressable by thefile system (e.g., an archive file) and (2) a subset of such a file.

As will be described in further detail, it can also be useful inperforming certain functions of the information management system 100 toaccess and modify metadata within the primary data 112. Metadatagenerally includes information about data objects or characteristicsassociated with the data objects.

Metadata can include, without limitation, one or more of the following:the data owner (e.g., the client or user that generates the data), thelast modified time (e.g., the time of the most recent modification ofthe data object), a data object name (e.g., a file name), a data objectsize (e.g., a number of bytes of data), information about the content(e.g., an indication as to the existence of a particular search term),to/from information for email (e.g., an email sender, recipient, etc.),creation date, file type (e.g., format or application type), lastaccessed time, application type (e.g., type of application thatgenerated the data object), location/network (e.g., a current, past orfuture location of the data object and network pathways to/from the dataobject), frequency of change (e.g., a period in which the data object ismodified), business unit (e.g., a group or department that generates,manages or is otherwise associated with the data object), and aginginformation (e.g., a schedule, such as a time period, in which the dataobject is migrated to secondary or long term storage), boot sectors,partition layouts, file location within a file folder directorystructure, user permissions, owners, groups, access control lists[ACLs]), system metadata (e.g., registry information), combinations ofthe same or the like.

In addition to metadata generated by or related to file systems andoperating systems, some of the applications 110 maintain indices ofmetadata for data objects, e.g., metadata associated with individualemail messages. Thus, each data object may be associated withcorresponding metadata. The use of metadata to perform classificationand other functions is described in greater detail below.

Each of the client computing devices 102 are associated with and/or incommunication with one or more of the primary storage devices 104storing corresponding primary data 112. A client computing device 102may be considered to be “associated with” or “in communication with” aprimary storage device 104 if it is capable of one or more of: storingdata to the primary storage device 104, retrieving data from the primarystorage device 104, and modifying data retrieved from a primary storagedevice 104.

The primary storage devices 104 can include, without limitation, diskdrives, hard-disk arrays, semiconductor memory (e.g., solid statedrives), and network attached storage (NAS) devices. In some cases, theprimary storage devices 104 form part of a distributed file system. Theprimary storage devices 104 may have relatively fast I/O times and/orare relatively expensive in comparison to the secondary storage devices108. For example, the information management system 100 may generallyregularly access data and metadata stored on primary storage devices104, whereas data and metadata stored on the secondary storage devices108 is accessed relatively less frequently.

In some cases, each primary storage device 104 is dedicated to anassociated client computing devices 102. For instance, a primary storagedevice 104 in one embodiment is a local disk drive of a correspondingclient computing device 102. In other cases, one or more primary storagedevices 104 can be shared by multiple client computing devices 102. Asone example, a primary storage device 104 can be a disk array shared bya group of client computing devices 102, such as one of the followingtypes of disk arrays: EMC Clariion, EMC Symmetrix, EMC Celerra, DellEqualLogic, IBM XIV, NetApp FAS, HP EVA, and HP 3PAR.

The information management system 100 may also include hosted services(not shown), which may be hosted in some cases by an entity other thanthe organization that employs the other components of the informationmanagement system 100. For instance, the hosted services may be providedby various online service providers to the organization. Such serviceproviders can provide services including social networking services,hosted email services, or hosted productivity applications or otherhosted applications).

Hosted services may include software-as-a-service (SaaS),platform-as-a-service (PaaS), application service providers (ASPs),cloud services, or other mechanisms for delivering functionality via anetwork. As it provides services to users, each hosted service maygenerate additional data and metadata under management of theinformation management system 100, e.g., as primary data 112. In somecases, the hosted services may be accessed using one of the applications110. As an example, a hosted mail service may be accessed via browserrunning on a client computing device 102.

Secondary Copies and Exemplary Secondary Storage Devices

The primary data 112 stored on the primary storage devices 104 may becompromised in some cases, such as when an employee deliberately oraccidentally deletes or overwrites primary data 112 during their normalcourse of work. Or the primary storage devices 104 can be damaged orotherwise corrupted.

For recovery and/or regulatory compliance purposes, it is thereforeuseful to generate copies of the primary data 112. Accordingly, theinformation management system 100 includes one or more secondary storagecomputing devices 106 and one or more secondary storage devices 108configured to create and store one or more secondary copies 116 of theprimary data 112 and associated metadata. The secondary storagecomputing devices 106 and the secondary storage devices 108 may bereferred to in some cases as a secondary storage subsystem 118.

Creation of secondary copies 116 can help meet information managementgoals, such as: restoring data and/or metadata if an original version(e.g., of primary data 112) is lost (e.g., by deletion, corruption, ordisaster); allowing point-in-time recovery; complying with regulatorydata retention and electronic discovery (e-discovery) requirements;reducing utilized storage capacity; facilitating organization and searchof data; improving user access to data files across multiple computingdevices and/or hosted services; and implementing data retentionpolicies.

Types of secondary copy operations can include, without limitation,backup operations, archive operations, snapshot operations, replicationoperations (e.g., continuous data replication [CDR]), data retentionpolicies such as information lifecycle management and hierarchicalstorage management operations, and the like. These specific typesoperations are discussed in greater detail below.

Regardless of the type of secondary copy operation, the client computingdevices 102 access or receive primary data 112 and communicate the data,e.g., over the communication pathways 114, for storage in the secondarystorage device(s) 108.

A secondary copy 116 can comprise a separate stored copy of applicationdata that is derived from one or more earlier created, stored copies(e.g., derived from primary data 112 or another secondary copy 116).Secondary copies 116 can include point-in-time data, and may be intendedfor relatively long-term retention (e.g., weeks, months or years),before some or all of the data is moved to other storage or isdiscarded.

In some cases, a secondary copy 116 is a copy of application datacreated and stored subsequent to at least one other stored instance(e.g., subsequent to corresponding primary data 112 or to anothersecondary copy 116), in a different storage device than at least oneprevious stored copy, and/or remotely from at least one previous storedcopy. Secondary copies 116 may be stored in relatively slow and/or lowcost storage (e.g., magnetic tape). A secondary copy 116 may be storedin a backup or archive format, or in some other format different thanthe native source application format or other primary data format.

In some cases, secondary copies 116 are indexed so users can browse andrestore at another point in time. After creation of a secondary copy 116representative of certain primary data 112, a pointer or other locationindicia (e.g., a stub) may be placed in primary data 112, or beotherwise associated with primary data 112 to indicate the currentlocation on the secondary storage device(s) 108.

Since an instance a data object or metadata in primary data 112 maychange over time as it is modified by an application 110 (or hostedservice or the operating system), the information management system 100may create and manage multiple secondary copies 116 of a particular dataobject or metadata, each representing the state of the data object inprimary data 112 at a particular point in time. Moreover, since aninstance of a data object in primary data 112 may eventually be deletedfrom the primary storage device 104 and the file system, the informationmanagement system 100 may continue to manage point-in-timerepresentations of that data object, even though the instance in primarydata 112 no longer exists.

For virtualized computing devices the operating system and otherapplications 110 of the client computing device(s) 102 may executewithin or under the management of virtualization software (e.g., a VMM),and the primary storage device(s) 104 may comprise a virtual diskcreated on a physical storage device. The information management system100 may create secondary copies 116 of the files or other data objectsin a virtual disk file and/or secondary copies 116 of the entire virtualdisk file itself (e.g., of an entire .vmdk file).

Secondary copies 116 may be distinguished from corresponding primarydata 112 in a variety of ways, some of which will now be described.First, as discussed, secondary copies 116 can be stored in a differentformat (e.g., backup, archive, or other non-native format) than primarydata 112. For this or other reasons, secondary copies 116 may not bedirectly useable by the applications 110 of the client computing device102, e.g., via standard system calls or otherwise without modification,processing, or other intervention by the information management system100.

Secondary copies 116 are also often stored on a secondary storage device108 that is inaccessible to the applications 110 running on the clientcomputing devices 102 (and/or hosted services). Some secondary copies116 may be “offline copies,” in that they are not readily available(e.g. not mounted to tape or disk). Offline copies can include copies ofdata that the information management system 100 can access without humanintervention (e.g. tapes within an automated tape library, but not yetmounted in a drive), and copies that the information management system100 can access only with at least some human intervention (e.g. tapeslocated at an offsite storage site).

The secondary storage devices 108 can include any suitable type ofstorage device such as, without limitation, one or more tape libraries,disk drives or other magnetic, non-tape storage devices, optical mediastorage devices, solid state storage devices, NAS devices, combinationsof the same, and the like. In some cases, the secondary storage devices108 are provided in a cloud (e.g. a private cloud or one operated by athird-party vendor).

The secondary storage device(s) 108 in some cases comprises a disk arrayor a portion thereof. In some cases, a single storage device (e.g., adisk array) is used for storing both primary data 112 and at least somesecondary copies 116. In one example, a disk array capable of performinghardware snapshots stores primary data 112 and creates and storeshardware snapshots of the primary data 112 as secondary copies 116.

The Use of Intermediary Devices for Creating Secondary Copies

Creating secondary copies can be a challenging task. For instance, therecan be hundreds or thousands of client computing devices 102 continuallygenerating large volumes of primary data 112 to be protected. Also,there can be significant overhead involved in the creation of secondarycopies 116. Moreover, secondary storage devices 108 may be specialpurpose components, and interacting with them can require specializedintelligence.

In some cases, the client computing devices 102 interact directly withthe secondary storage device 108 to create the secondary copies 116.However, in view of the factors described above, this approach cannegatively impact the ability of the client computing devices 102 toserve the applications 110 and produce primary data 112. Further, theclient computing devices 102 may not be optimized for interaction withthe secondary storage devices 108.

Thus, in some embodiments, the information management system 100includes one or more software and/or hardware components which generallyact as intermediaries between the client computing devices 102 and thesecondary storage devices 108. In addition to off-loading certainresponsibilities from the client computing devices 102, theseintermediary components can provide other benefits. For instance, asdiscussed further below with respect to FIG. 1D, distributing some ofthe work involved in creating secondary copies 116 can enhancescalability.

The intermediary components can include one or more secondary storagecomputing devices 106 as shown in FIG. 1A and/or one or more mediaagents, which can be software modules residing on correspondingsecondary storage computing devices 106 (or other appropriate devices).Media agents are discussed below (e.g., with respect to FIGS. 1C-1E).

The secondary storage computing device(s) 106 can comprise anyappropriate type of computing device and can include, withoutlimitation, any of the types of fixed and portable computing devicesdescribed above with respect to the client computing devices 102. Insome cases, the secondary storage computing device(s) 106 includespecialized hardware and/or software componentry for interacting withthe secondary storage devices 108.

To create a secondary copy 116, the client computing device 102communicates the primary data 112 to be copied (or a processed versionthereof) to the designated secondary storage computing device 106, viathe communication pathway 114. The secondary storage computing device106 in turn conveys the received data (or a processed version thereof)to the secondary storage device 108. In some such configurations, thecommunication pathway 114 between the client computing device 102 andthe secondary storage computing device 106 comprises a portion of a LAN,WAN or SAN. In other cases, at least some client computing devices 102communicate directly with the secondary storage devices 108 (e.g., viaFibre Channel or SCSI connections).

Exemplary Primary Data and an Exemplary Secondary Copy

FIG. 1B is a detailed view showing some specific examples of primarydata stored on the primary storage device(s) 104 and secondary copy datastored on the secondary storage device(s) 108, with other components inthe system removed for the purposes of illustration. Stored on theprimary storage device(s) 104 are primary data objects including wordprocessing documents 119A-B, spreadsheets 120, presentation documents122, video files 124, image files 126, email mailboxes 128 (andcorresponding email messages 129A-C), html/xml or other types of markuplanguage files 130, databases 132 and corresponding tables 133A-133C).

Some or all primary data objects are associated with a primary copy ofobject metadata (e.g., “Meta1-11”), which may be file system metadataand/or application specific metadata. Stored on the secondary storagedevice(s) 108 are secondary copy objects 134A-C which may include copiesof or otherwise represent corresponding primary data objects andmetadata.

As shown, the secondary copy objects 134A-C can individually representmore than one primary data object. For example, secondary copy dataobject 134A represents three separate primary data objects 133C, 122 and129C (represented as 133C′, 122′ and 129C′, respectively). Moreover, asindicated by the prime mark (′), a secondary copy object may store arepresentation of a primary data object or metadata differently than theoriginal format, e.g., in a compressed, encrypted, deduplicated, orother modified format.

Exemplary Information Management System Architecture

The information management system 100 can incorporate a variety ofdifferent hardware and software components, which can in turn beorganized with respect to one another in many different configurations,depending on the embodiment. There are critical design choices involvedin specifying the functional responsibilities of the components and therole of each component in the information management system 100. Forinstance, as will be discussed, such design choices can impactperformance as well as the adaptability of the information managementsystem 100 to data growth or other changing circumstances.

FIG. 1C shows an information management system 100 designed according tothese considerations and which includes: a central storage orinformation manager 140 configured to perform certain control functions,one or more data agents 142 executing on the client computing device(s)102 configured to process primary data 112, and one or more media agents144 executing on the one or more secondary storage computing devices 106for performing tasks involving the secondary storage devices 108.

Storage Manager

As noted, the number of components in the information management system100 and the amount of data under management can be quite large. Managingthe components and data is therefore a significant task, and a task thatcan grow in an often unpredictable fashion as the quantity of componentsand data scale to meet the needs of the organization.

For these and other reasons, according to certain embodiments,responsibility for controlling the information management system 100, orat least a significant portion of that responsibility, is allocated tothe storage manager 140.

By distributing control functionality in this manner, the storagemanager 140 can be adapted independently according to changingcircumstances. Moreover, a host computing device can be selected to bestsuit the functions of the storage manager 140. These and otheradvantages are described in further detail below with respect to FIG.1D.

The storage manager 140 may be a software module or other application.The storage manager generally initiates, coordinates and/or controlsstorage and other information management operations performed by theinformation management system 100, e.g., to protect and control theprimary data 112 and secondary copies 116 of data and metadata.

As shown by the dashed, arrowed lines, the storage manager 140 maycommunicate with and/or control some or all elements of the informationmanagement system 100, such as the data agents 142 and media agents 144.Thus, in certain embodiments, control information originates from thestorage manager 140, whereas payload data and metadata is generallycommunicated between the data agents 142 and the media agents 144 (orotherwise between the client computing device(s) 102 and the secondarystorage computing device(s) 106), e.g., at the direction of the storagemanager 140. In other embodiments, some information managementoperations are controlled by other components in the informationmanagement system 100 (e.g., the media agent(s) 144 or data agent(s)142), instead of or in combination with the storage manager 140.

According to certain embodiments, the storage manager provides one ormore of the following functions:

-   -   initiating execution of secondary copy operations;    -   managing secondary storage devices 108 and inventory/capacity of        the same;    -   allocating secondary storage devices 108 for secondary storage        operations;    -   monitoring completion of and providing status reporting related        to secondary storage operations;    -   tracking age information relating to secondary copies 116,        secondary storage devices 108, and comparing the age information        against retention guidelines;    -   tracking movement of data within the information management        system 100;    -   tracking logical associations between components in the        information management system 100;    -   protecting metadata associated with the information management        system 100; and    -   implementing operations management functionality.

The storage manager 140 may maintain a database 146 ofmanagement-related data and information management policies 148. Thedatabase 146 may include a management index 150 or other data structurethat stores logical associations between components of the system, userpreferences and/or profiles (e.g., preferences regarding encryption,compression, or deduplication of primary or secondary copy data,preferences regarding the scheduling, type, or other aspects of primaryor secondary copy or other operations, mappings of particularinformation management users or user accounts to certain computingdevices or other components, etc.), management tasks, mediacontainerization, or other useful data. For example, the storage manager140 may use the index 150 to track logical associations between mediaagents 144 and secondary storage devices 108 and/or movement of datafrom primary storage devices 104 to secondary storage devices 108.

Administrators and other employees may be able to manually configure andinitiate certain information management operations on an individualbasis. But while this may be acceptable for some recovery operations orother relatively less frequent tasks, it is often not workable forimplementing on-going organization-wide data protection and management.

Thus, the information management system 100 may utilize informationmanagement policies 148 for specifying and executing informationmanagement operations (e.g., on an automated basis). Generally, aninformation management policy 148 can include a data structure or otherinformation source that specifies a set of parameters (e.g., criteriaand rules) associated with storage or other information managementoperations.

The storage manager database 146 may maintain the information managementpolicies 148 and associated data, although the information managementpolicies 148 can be stored in any appropriate location. For instance, astorage policy may be stored as metadata in a media agent database 152or in a secondary storage device 108 (e.g., as an archive copy) for usein restore operations or other information management operations,depending on the embodiment. Information management policies 148 aredescribed further below.

According to certain embodiments, the storage manager database 146comprises a relational database (e.g., an SQL database) for trackingmetadata, such as metadata associated with secondary copy operations(e.g., what client computing devices 102 and corresponding data wereprotected). This and other metadata may additionally be stored in otherlocations, such as at the secondary storage computing devices 106 or onthe secondary storage devices 108, allowing data recovery without theuse of the storage manager 140.

As shown, the storage manager 140 may include a jobs agent 156, a userinterface 158, and a management agent 154, all of which may beimplemented as interconnected software modules or application programs.

The jobs agent 156 in some embodiments initiates, controls, and/ormonitors the status of some or all storage or other informationmanagement operations previously performed, currently being performed,or scheduled to be performed by the information management system 100.For instance, the jobs agent 156 may access information managementpolicies 148 to determine when and how to initiate and control secondarycopy and other information management operations, as will be discussedfurther.

The user interface 158 may include information processing and displaysoftware, such as a graphical user interface (“GUI”), an applicationprogram interface (“API”), or other interactive interface through whichusers and system processes can retrieve information about the status ofinformation management operations (e.g., storage operations) or issueinstructions to the information management system 100 and itsconstituent components.

The storage manager 140 may also track information that permits it toselect, designate, or otherwise identify content indices, deduplicationdatabases, or similar databases or resources or data sets within itsinformation management cell (or another cell) to be searched in responseto certain queries. Such queries may be entered by the user viainteraction with the user interface 158.

Via the user interface 158, users may optionally issue instructions tothe components in the information management system 100 regardingperformance of storage and recovery operations. For example, a user maymodify a schedule concerning the number of pending secondary copyoperations. As another example, a user may employ the GUI to view thestatus of pending storage operations or to monitor the status of certaincomponents in the information management system 100 (e.g., the amount ofcapacity left in a storage device).

In general, the management agent 154 allows multiple informationmanagement systems 100 to communicate with one another. For example, theinformation management system 100 in some cases may be one informationmanagement subsystem or “cell” of a network of multiple cells adjacentto one another or otherwise logically related in a WAN or LAN. With thisarrangement, the cells may be connected to one another throughrespective management agents 154.

For instance, the management agent 154 can provide the storage manager140 with the ability to communicate with other components within theinformation management system 100 (and/or other cells within a largerinformation management system) via network protocols and applicationprogramming interfaces (“APIs”) including, e.g., HTTP, HTTPS, FTP, REST,virtualization software APIs, cloud service provider APIs, and hostedservice provider APIs. Inter-cell communication and hierarchy isdescribed in greater detail in U.S. Pat. No. 7,035,880, which isincorporated by reference herein.

Data Agents

As discussed, a variety of different types of applications 110 canreside on a given client computing device 102, including operatingsystems, database applications, e-mail applications, and virtualmachines, just to name a few. And, as part of the as part of the processof creating and restoring secondary copies 116, the client computingdevices 102 may be tasked with processing and preparing the primary data112 from these various different applications 110. Moreover, the natureof the processing/preparation can differ across clients and applicationtypes, e.g., due to inherent structural and formatting differencesbetween applications 110.

The one or more data agent(s) 142 are therefore advantageouslyconfigured in some embodiments to assist in the performance ofinformation management operations based on the type of data that isbeing protected, at a client-specific and/or application-specific level.

The data agent 142 may be a software module or component that isgenerally responsible for managing, initiating, or otherwise assistingin the performance of information management operations. For instance,the data agent 142 may take part in performing data storage operationssuch as the copying, archiving, migrating, replicating of primary data112 stored in the primary storage device(s) 104. The data agent 142 mayreceive control information from the storage manager 140, such ascommands to transfer copies of data objects, metadata, and other payloaddata to the media agents 144.

In some embodiments, a data agent 142 may be distributed between theclient computing device 102 and storage manager 140 (and any otherintermediate components) or may be deployed from a remote location orits functions approximated by a remote process that performs some or allof the functions of data agent 142. In addition, a data agent 142 mayperform some functions provided by a media agent 144, e.g., encryptionand deduplication.

As indicated, each data agent 142 may be specialized for a particularapplication 110, and the system can employ multiple data agents 142,each of which may backup, migrate, and recover data associated with adifferent application 110. For instance, different individual dataagents 142 may be designed to handle Microsoft Exchange data, LotusNotes data, Microsoft Windows file system data, Microsoft ActiveDirectory Objects data, SQL Server data, SharePoint data, Oracledatabase data, SAP database data, virtual machines and/or associateddata, and other types of data.

A file system data agent, for example, may handle data files and/orother file system information. If a client computing device 102 has twoor more types of data, one data agent 142 may be used for each data typeto copy, archive, migrate, and restore the client computing device 102data. For example, to backup, migrate, and restore all of the data on aMicrosoft Exchange server, the client computing device 102 may use oneMicrosoft Exchange Mailbox data agent 142 to backup the Exchangemailboxes, one Microsoft Exchange Database data agent 142 to backup theExchange databases, one Microsoft Exchange Public Folder data agent 142to backup the Exchange Public Folders, and one Microsoft Windows FileSystem data agent 142 to backup the file system of the client computingdevice 102. In such embodiments, these data agents 142 may be treated asfour separate data agents 142 even though they reside on the same clientcomputing device 102.

Other embodiments may employ one or more generic data agents 142 thatcan handle and process data from two or more different applications 110,or that can handle and process multiple data types, instead of or inaddition to using specialized data agents 142. For example, one genericdata agent 142 may be used to back up, migrate and restore MicrosoftExchange Mailbox data and Microsoft Exchange Database data while anothergeneric data agent may handle Microsoft Exchange Public Folder data andMicrosoft Windows File System data.

Each data agent 142 may be configured to access data and/or metadatastored in the primary storage device(s) 104 associated with the dataagent 142 and process the data as appropriate. For example, during asecondary copy operation, the data agent 142 may arrange or assemble thedata and metadata into one or more files having a certain format (e.g.,a particular backup or archive format) before transferring the file(s)to a media agent 144 or other component. The file(s) may include a listof files or other metadata. Each data agent 142 can also assist inrestoring data or metadata to primary storage devices 104 from asecondary copy 116. For instance, the data agent 142 may operate inconjunction with the storage manager 140 and one or more of the mediaagents 144 to restore data from secondary storage device(s) 108.

Media Agents

As indicated above with respect to FIG. 1A, off-loading certainresponsibilities from the client computing devices 102 to intermediarycomponents such as the media agent(s) 144 can provide a number ofbenefits including improved client computing device 102 operation,faster secondary copy operation performance, and enhanced scalability.As one specific example which will be discussed below in further detail,the media agent 144 can act as a local cache of copied data and/ormetadata that it has stored to the secondary storage device(s) 108,providing improved restore capabilities.

Generally speaking, a media agent 144 may be implemented as a softwaremodule that manages, coordinates, and facilitates the transmission ofdata, as directed by the storage manager 140, between a client computingdevice 102 and one or more secondary storage devices 108. Whereas thestorage manager 140 controls the operation of the information managementsystem 100, the media agent 144 generally provides a portal to secondarystorage devices 108.

Media agents 144 can comprise logically and/or physically separate nodesin the information management system 100 (e.g., separate from the clientcomputing devices 102, storage manager 140, and/or secondary storagedevices 108). In addition, each media agent 144 may reside on adedicated secondary storage computing device 106 in some cases, while inother embodiments a plurality of media agents 144 reside on the samesecondary storage computing device 106.

A media agent 144 (and corresponding media agent database 152) may beconsidered to be “associated with” a particular secondary storage device108 if that media agent 144 is capable of one or more of: routing and/orstoring data to the particular secondary storage device 108,coordinating the routing and/or storing of data to the particularsecondary storage device 108, retrieving data from the particularsecondary storage device 108, and coordinating the retrieval of datafrom a particular secondary storage device 108.

While media agent(s) 144 are generally associated with one or moresecondary storage devices 108, the media agents 144 in certainembodiments are physically separate from the secondary storage devices108. For instance, the media agents 144 may reside on secondary storagecomputing devices 106 having different housings or packages than thesecondary storage devices 108. In one example, a media agent 144 resideson a first server computer and is in communication with a secondarystorage device(s) 108 residing in a separate, rack-mounted RAID-basedsystem.

In operation, a media agent 144 associated with a particular secondarystorage device 108 may instruct the secondary storage device 108 (e.g.,a tape library) to use a robotic arm or other retrieval means to load oreject a certain storage media, and to subsequently archive, migrate, orretrieve data to or from that media, e.g., for the purpose of restoringthe data to a client computing device 102. The media agent 144 maycommunicate with a secondary storage device 108 via a suitablecommunications link, such as a SCSI or Fiber Channel link.

As shown, each media agent 144 may maintain an associated media agentdatabase 152. The media agent database 152 may be stored in a disk orother storage device (not shown) that is local to the secondary storagecomputing device 106 on which the media agent 144 resides. In othercases, the media agent database 152 is stored remotely from thesecondary storage computing device 106.

The media agent database 152 can include, among other things, an index153 including data generated during secondary copy operations and otherstorage or information management operations. The index 153 provides amedia agent 144 or other component with a fast and efficient mechanismfor locating secondary copies 116 or other data stored in the secondarystorage devices 108. In one configuration, a storage manager index 150or other data structure may store data associating a client computingdevice 102 with a particular media agent 144 and/or secondary storagedevice 108, as specified in a storage policy. A media agent index 153 orother data structure associated with the particular media agent 144 mayin turn include information about the stored data.

For instance, for each secondary copy 116, the index 153 may includemetadata such as a list of the data objects (e.g., files/subdirectories,database objects, mailbox objects, etc.), a path to the secondary copy116 on the corresponding secondary storage device 108, locationinformation indicating where the data objects are stored in thesecondary storage device 108, when the data objects were created ormodified, etc. Thus, the index 153 includes metadata associated with thesecondary copies 116 that is readily available for use in storageoperations and other activities without having to be first retrievedfrom the secondary storage device 108. In yet further embodiments, someor all of the data in the index 153 may instead or additionally bestored along with the data in a secondary storage device 108, e.g., witha copy of the index 153.

Because the index 153 maintained in the database 152 may operate as acache, it can also be referred to as an index cache. In such cases,information stored in the index cache 153 typically comprises data thatreflects certain particulars about storage operations that have occurredrelatively recently. After some triggering event, such as after acertain period of time elapses, or the index cache 153 reaches aparticular size, the index cache 153 may be copied or migrated to asecondary storage device(s) 108. This information may need to beretrieved and uploaded back into the index cache 153 or otherwiserestored to a media agent 144 to facilitate retrieval of data from thesecondary storage device(s) 108. In some embodiments, the cachedinformation may include format or containerization information relatedto archives or other files stored on the storage device(s) 108. In thismanner, the index cache 153 allows for accelerated restores.

In some alternative embodiments the media agent 144 generally acts as acoordinator or facilitator of storage operations between clientcomputing devices 102 and corresponding secondary storage devices 108,but does not actually write the data to the secondary storage device108. For instance, the storage manager 140 (or the media agent 144) mayinstruct a client computing device 102 and secondary storage device 108to communicate with one another directly. In such a case the clientcomputing device 102 transmits the data directly to the secondarystorage device 108 according to the received instructions, and viceversa. In some such cases, the media agent 144 may still receive,process, and/or maintain metadata related to the storage operations.Moreover, in these embodiments, the payload data can flow through themedia agent 144 for the purposes of populating the index cache 153maintained in the media agent database 152, but not for writing to thesecondary storage device 108.

The media agent 144 and/or other components such as the storage manager140 may in some cases incorporate additional functionality, such as dataclassification, content indexing, deduplication, encryption,compression, and the like. Further details regarding these and otherfunctions are described below.

Distributed, Scalable Architecture

As described, certain functions of the information management system 100can be distributed amongst various physical and/or logical components inthe system. For instance, one or more of the storage manager 140, dataagents 142, and media agents 144 may reside on computing devices thatare physically separate from one another. This architecture can providea number of benefits.

For instance, hardware and software design choices for each distributedcomponent can be targeted to suit its particular function. The secondarycomputing devices 106 on which the media agents 144 reside can betailored for interaction with associated secondary storage devices 108and provide fast index cache operation, among other specific tasks.Similarly, the client computing device(s) 102 can be selected toeffectively service the applications 110 residing thereon, in order toefficiently produce and store primary data 112.

Moreover, in some cases, one or more of the individual components in theinformation management system 100 can be distributed to multiple,separate computing devices. As one example, for large file systems wherethe amount of data stored in the storage management database 146 isrelatively large, the management database 146 may be migrated to orotherwise reside on a specialized database server (e.g., an SQL server)separate from a server that implements the other functions of thestorage manager 140. This configuration can provide added protectionbecause the database 146 can be protected with standard databaseutilities (e.g., SQL log shipping or database replication) independentfrom other functions of the storage manager 140. The database 146 can beefficiently replicated to a remote site for use in the event of adisaster or other data loss incident at the primary site. Or thedatabase 146 can be replicated to another computing device within thesame site, such as to a higher performance machine in the event that astorage manager host device can no longer service the needs of a growinginformation management system 100.

The distributed architecture also provides both scalability andefficient component utilization. FIG. 1D shows an embodiment of theinformation management system 100 including a plurality of clientcomputing devices 102 and associated data agents 142 as well as aplurality of secondary storage computing devices 106 and associatedmedia agents 144.

Additional components can be added or subtracted based on the evolvingneeds of the information management system 100. For instance, dependingon where bottlenecks are identified, administrators can add additionalclient computing devices 102, secondary storage devices 106 (andcorresponding media agents 144), and/or secondary storage devices 108.

Moreover, each client computing device 102 in some embodiments cancommunicate with any of the media agents 144, e.g., as directed by thestorage manager 140. And each media agent 144 may be able to communicatewith any of the secondary storage devices 108, e.g., as directed by thestorage manager 140. Thus, operations can be routed to the secondarystorage devices 108 in a dynamic and highly flexible manner. Furtherexamples of scalable systems capable of dynamic storage operations areprovided in U.S. Pat. No. 7,246,207, which is incorporated by referenceherein.

In alternative configurations, certain components are not distributedand may instead reside and execute on the same computing device. Forexample, in some embodiments one or more data agents 142 and the storagemanager 140 reside on the same client computing device 102. In anotherembodiment, one or more data agents 142 and one or more media agents 144reside on a single computing device.

Exemplary Types of Information Management Operations

In order to protect and leverage stored data, the information managementsystem 100 can be configured to perform a variety of informationmanagement operations. As will be described, these operations cangenerally include secondary copy and other data movement operations,processing and data manipulation operations, and management operations.

Data Movement Operations

Data movement operations according to certain embodiments are generallyoperations that involve the copying or migration of data (e.g., payloaddata) between different locations in the information management system100. For example, data movement operations can include operations inwhich stored data is copied, migrated, or otherwise transferred fromprimary storage device(s) 104 to secondary storage device(s) 108, fromsecondary storage device(s) 108 to different secondary storage device(s)108, or from primary storage device(s) 104 to different primary storagedevice(s) 104.

Data movement operations can include by way of example, backupoperations, archive operations, information lifecycle managementoperations such as hierarchical storage management operations,replication operations (e.g., continuous data replication operations),snapshot operations, deduplication operations, single-instancingoperations, auxiliary copy operations, and the like. As will bediscussed, some of these operations involve the copying, migration orother movement of data, without actually creating multiple, distinctcopies. Nonetheless, some or all of these operations are referred to as“copy” operations for simplicity.

Backup Operations

A backup operation creates a copy of primary data 112 at a particularpoint in time. Each subsequent backup copy may be maintainedindependently of the first. Further, a backup copy in some embodimentsis stored in a backup format. This can be in contrast to the version inprimary data 112 from which the backup copy is derived, and which mayinstead be stored in a native format of the source application(s) 110.In various cases, backup copies can be stored in a format in which thedata is compressed, encrypted, deduplicated, and/or otherwise modifiedfrom the original application format. For example, a backup copy may bestored in a backup format that facilitates compression and/or efficientlong-term storage.

Backup copies can have relatively long retention periods as compared toprimary data 112, and may be stored on media with slower retrieval timesthan primary data 112 and certain other types of secondary copies 116.On the other hand, backups may have relatively shorter retention periodsthan some other types of secondary copies 116, such as archive copies(described below). Backups may sometimes be stored at on offsitelocation.

Backup operations can include full, synthetic or incremental backups. Afull backup in some embodiments is generally a complete image of thedata to be protected. However, because full backup copies can consume arelatively large amount of storage, it can be useful to use a fullbackup copy as a baseline and only store changes relative to the fullbackup copy for subsequent backup copies.

For instance, a differential backup operation (or cumulative incrementalbackup operation) tracks and stores changes that have occurred since thelast full backup. Differential backups can grow quickly in size, but canprovide relatively efficient restore times because a restore can becompleted in some cases using only the full backup copy and the latestdifferential copy.

An incremental backup operation generally tracks and stores changessince the most recent backup copy of any type, which can greatly reducestorage utilization. In some cases, however, restore times can berelatively long in comparison to full or differential backups becausecompleting a restore operation may involve accessing a full backup inaddition to multiple incremental backups.

Any of the above types of backup operations can be at the file-level,e.g., where the information management system 100 generally trackschanges to files at the file-level, and includes copies of files in thebackup copy. In other cases, block-level backups are employed, wherefiles are broken into constituent blocks, and changes are tracked at theblock-level. Upon restore, the information management system 100reassembles the blocks into files in a transparent fashion.

Far less data may actually be transferred and copied to the secondarystorage devices 108 during a block-level copy than during a file-levelcopy, resulting in faster execution times. However, when restoring ablock-level copy, the process of locating constituent blocks cansometimes result in longer restore times as compared to file-levelbackups. Similar to backup operations, the other types of secondary copyoperations described herein can also be implemented at either thefile-level or the block-level.

Archive Operations

Because backup operations generally involve maintaining a version of thecopied data in primary data 112 and also maintaining backup copies insecondary storage device(s) 108, they can consume significant storagecapacity. To help reduce storage consumption, an archive operationaccording to certain embodiments creates a secondary copy 116 by bothcopying and removing source data. Or, seen another way, archiveoperations can involve moving some or all of the source data to thearchive destination. Thus, data satisfying criteria for removal (e.g.,data of a threshold age or size) from the source copy may be removedfrom source storage. Archive copies are sometimes stored in an archiveformat or other non-native application format. The source data may beprimary data 112 or a secondary copy 116, depending on the situation. Aswith backup copies, archive copies can be stored in a format in whichthe data is compressed, encrypted, deduplicated, and/or otherwisemodified from the original application format.

In addition, archive copies may be retained for relatively long periodsof time (e.g., years) and, in some cases, are never deleted. Archivecopies are generally retained for longer periods of time than backupcopies, for example. In certain embodiments, archive copies may be madeand kept for extended periods in order to meet compliance regulations.

Moreover, when primary data 112 is archived, in some cases the archivedprimary data 112 or a portion thereof is deleted when creating thearchive copy. Thus, archiving can serve the purpose of freeing up spacein the primary storage device(s) 104. Similarly, when a secondary copy116 is archived, the secondary copy 116 may be deleted, and an archivecopy can therefore serve the purpose of freeing up space in secondarystorage device(s) 108. In contrast, source copies often remain intactwhen creating backup copies.

Snapshot Operations

Snapshot operations can provide a relatively lightweight, efficientmechanism for protecting data. From an end-user viewpoint, a snapshotmay be thought of as an “instant” image of the primary data 112 at agiven point in time. In one embodiment, a snapshot may generally capturethe directory structure of an object in primary data 112 such as a fileor volume or other data set at a particular moment in time and may alsopreserve file attributes and contents. A snapshot in some cases iscreated relatively quickly, e.g., substantially instantly, using aminimum amount of file space, but may still function as a conventionalfile system backup.

A snapshot copy in many cases can be made quickly and withoutsignificantly impacting primary computing resources because largeamounts of data need not be copied or moved. In some embodiments, asnapshot may exist as a virtual file system, parallel to the actual filesystem. Users in some cases gain read-only access to the record of filesand directories of the snapshot. By electing to restore primary data 112from a snapshot taken at a given point in time, users may also returnthe current file system to the state of the file system that existedwhen the snapshot was taken.

Some types of snapshots do not actually create another physical copy ofall the data as it existed at the particular point in time, but maysimply create pointers that are able to map files and directories tospecific memory locations (e.g., disk blocks) where the data resides, asit existed at the particular point in time. For example, a snapshot copymay include a set of pointers derived from the file system or anapplication. Each pointer points to a respective stored data block, socollectively, the set of pointers reflect the storage location and stateof the data object (e.g., file(s) or volume(s) or data set(s)) at aparticular point in time when the snapshot copy was created.

In some embodiments, once a snapshot has been taken, subsequent changesto the file system typically do not overwrite the blocks in use at thetime of the snapshot. Therefore, the initial snapshot may use only asmall amount of disk space needed to record a mapping or other datastructure representing or otherwise tracking the blocks that correspondto the current state of the file system. Additional disk space isusually required only when files and directories are actually modifiedlater. Furthermore, when files are modified, typically only the pointerswhich map to blocks are copied, not the blocks themselves. In someembodiments, for example in the case of “copy-on-write” snapshots, whena block changes in primary storage, the block is copied to secondarystorage or cached in primary storage before the block is overwritten inprimary storage. The snapshot mapping of file system data is alsoupdated to reflect the changed block(s) at that particular point intime. In some other cases, a snapshot includes a full physical copy ofall or substantially all of the data represented by the snapshot.Further examples of snapshot operations are provided in U.S. Pat. No.7,529,782, which is incorporated by reference herein.

Replication Operations

Another type of secondary copy operation is a replication operation.Some types of secondary copies 116 are used to periodically captureimages of primary data 112 at particular points in time (e.g., backups,archives, and snapshots). However, it can also be useful for recoverypurposes to protect primary data 112 in a more continuous fashion, byreplicating the primary data 112 substantially as changes occur. In somecases a replication copy can be a mirror copy, for instance, wherechanges made to primary data 112 are mirrored to another location (e.g.,to secondary storage device(s) 108). By copying each write operation tothe replication copy, two storage systems are kept synchronized orsubstantially synchronized so that they are virtually identical atapproximately the same time. Where entire disk volumes are mirrored,however, mirroring can require significant amount of storage space andutilizes a large amount of processing resources.

According to some embodiments storage operations are performed onreplicated data that represents a recoverable state, or “known goodstate” of a particular application running on the source system. Forinstance, in certain embodiments, known good replication copies may beviewed as copies of primary data 112. This feature allows the system todirectly access, copy, restore, backup or otherwise manipulate thereplication copies as if the data was the “live”, primary data 112. Thiscan reduce access time, storage utilization, and impact on sourceapplications 110, among other benefits.

Based on known good state information, the information management system100 can replicate sections of application data that represent arecoverable state rather than rote copying of blocks of data. Examplesof compatible replication operations (e.g., continuous data replication)are provided in U.S. Pat. No. 7,617,262, which is incorporated byreference herein.

Deduplication/Single-Instancing Operations

Another type of data movement operation is deduplication, which isuseful to reduce the amount of data within the system. For instance,some or all of the above-described secondary storage operations caninvolve deduplication in some fashion. New data is read, broken downinto blocks (e.g., sub-file level blocks) of a selected granularity,compared with blocks that are already stored, and only the new blocksare stored. Blocks that already exist are represented as pointers to thealready stored data.

In order to stream-line the comparison process, the informationmanagement system 100 may calculate and/or store signatures (e.g.,hashes) corresponding to the individual data blocks and compare thehashes instead of comparing entire data blocks. In some cases, only asingle instance of each element is stored, and deduplication operationsmay therefore be referred to interchangeably as “single-instancing”operations. Depending on the implementation, however, deduplication orsingle-instancing operations can store more than one instance of certaindata blocks, but nonetheless significantly reduce data redundancy.Moreover, single-instancing in some cases is distinguished fromdeduplication as a process of analyzing and reducing data at the filelevel, rather than the sub-file level.

Depending on the embodiment, deduplication blocks can be of fixed orvariable length. Using variable length blocks can provide enhanceddeduplication by responding to changes in the data stream, but caninvolve complex processing. In some cases, the information managementsystem 100 utilizes a technique for dynamically aligning deduplicationblocks (e.g., fixed-length blocks) based on changing content in the datastream, as described in U.S. Pat. Pub. No. 2012/0084269, which isincorporated by reference herein.

The information management system 100 can perform deduplication in avariety of manners at a variety of locations in the informationmanagement system 100. For instance, in some embodiments, theinformation management system 100 implements “target-side” deduplicationby deduplicating data (e.g., secondary copies 116) stored in thesecondary storage devices 108. In some such cases, the media agents 144are generally configured to manage the deduplication process. Forinstance, one or more of the media agents 144 maintain a correspondingdeduplication database that stores deduplication information (e.g.,datablock signatures). Examples of such a configuration are provided inU.S. Pat. Pub. No. 2012/0150826, which is incorporated by referenceherein. Deduplication can also be performed on the “source-side” (or“client-side”), e.g., to reduce the amount of traffic between the mediaagents 144 and the client computing device(s) 102 and/or reduceredundant data stored in the primary storage devices 104. Examples ofsuch deduplication techniques are provided in U.S. Pat. Pub. No.2012/0150818, which is incorporated by reference herein.

Information Lifecycle Management and Hierarchical Storage ManagementOperations

In some embodiments, files and other data over their lifetime move frommore expensive, quick access storage to less expensive, slower accessstorage. Operations associated with moving data through various tiers ofstorage are sometimes referred to as information lifecycle management(ILM) operations.

One type of ILM operation is a hierarchical storage management (HSM)operation. A HSM operation is generally an operation for automaticallymoving data between classes of storage devices, such as betweenhigh-cost and low-cost storage devices. For instance, an HSM operationmay involve movement of data from primary storage devices 104 tosecondary storage devices 108, or between tiers of secondary storagedevices 108. With each tier, the storage devices may be progressivelyrelatively cheaper, have relatively slower access/restore times, etc.For example, movement of data between tiers may occur as data becomesless important over time.

In some embodiments, an HSM operation is similar to an archive operationin that creating an HSM copy may (though not always) involve deletingsome of the source data. For example, an HSM copy may include data fromprimary data 112 or a secondary copy 116 that is larger than a givensize threshold or older than a given age threshold and that is stored ina backup format.

Often, and unlike some types of archive copies, HSM data that is removedor aged from the source copy is replaced by a logical reference pointeror stub. The reference pointer or stub can be stored in the primarystorage device 104 to replace the deleted data in primary data 112 (orother source copy) and to point to or otherwise indicate the newlocation in a secondary storage device 108.

According to one example, files are generally moved between higher andlower cost storage depending on how often the files are accessed. When auser requests access to the HSM data that has been removed or migrated,the information management system 100 uses the stub to locate the dataand often make recovery of the data appear transparent, even though theHSM data may be stored at a location different from the remaining sourcedata. The stub may also include some metadata associated with thecorresponding data, so that a file system and/or application can providesome information about the data object and/or a limited-functionalityversion (e.g., a preview) of the data object.

An HSM copy may be stored in a format other than the native applicationformat (e.g., where the data is compressed, encrypted, deduplicated,and/or otherwise modified from the original application format). In somecases, copies which involve the removal of data from source storage andthe maintenance of stub or other logical reference information on sourcestorage may be referred to generally as “on-line archive copies”. On theother hand, copies which involve the removal of data from source storagewithout the maintenance of stub or other logical reference informationon source storage may be referred to as “off-line archive copies”.

Auxiliary Copy and Disaster Recovery Operations

An auxiliary copy is generally a copy operation in which a copy iscreated of an existing secondary copy 116. For instance, an initial or“primary” secondary copy 116 may be generated using or otherwise bederived from primary data 112, whereas an auxiliary copy is generatedfrom the initial secondary copy 116. Auxiliary copies can be used tocreate additional standby copies of data and may reside on differentsecondary storage devices 108 than initial secondary copies 116. Thus,auxiliary copies can be used for recovery purposes if initial secondarycopies 116 become unavailable. Exemplary compatible auxiliary copytechniques are described in further detail in U.S. Pat. No. 8,230,195,which is incorporated by reference herein.

The information management system 100 may also perform disaster recoveryoperations that make or retain disaster recovery copies, often assecondary, high-availability disk copies. The information managementsystem 100 may create secondary disk copies and store the copies atdisaster recovery locations using auxiliary copy or replicationoperations, such as continuous data replication technologies. Dependingon the particular data protection goals, disaster recovery locations canbe remote from the client computing devices 102 and primary storagedevices 104, remote from some or all of the secondary storage devices108, or both.

Data Processing and Manipulation Operations

As indicated, the information management system 100 can also beconfigured to implement certain data manipulation operations, whichaccording to certain embodiments are generally operations involving theprocessing or modification of stored data. Some data manipulationoperations include content indexing operations and classificationoperations can be useful in leveraging the data under management toprovide enhanced search and other features. Other data manipulationoperations such as compression and encryption can provide data reductionand security benefits, respectively.

Data manipulation operations can be different than data movementoperations in that they do not necessarily involve the copying,migration or other transfer of data (e.g., primary data 112 or secondarycopies 116) between different locations in the system. For instance,data manipulation operations may involve processing (e.g., offlineprocessing) or modification of already stored primary data 112 and/orsecondary copies 116. However, in some embodiments data manipulationoperations are performed in conjunction with data movement operations.As one example, the information management system 100 may encrypt datawhile performing an archive operation.

Content Indexing

In some embodiments, the information management system 100 “contentindexes” data stored within the primary data 112 and/or secondary copies116, providing enhanced search capabilities for data discovery and otherpurposes. The content indexing can be used to identify files or otherdata objects having pre-defined content (e.g., user-defined keywords orphrases), metadata (e.g., email metadata such as “to”, “from”, “cc”,“bcc”, attachment name, received time, etc.).

The information management system 100 generally organizes and cataloguesthe results in a content index, which may be stored within the mediaagent database 152, for example. The content index can also include thestorage locations of (or pointer references to) the indexed data in theprimary data 112 or secondary copies 116, as appropriate. The resultsmay also be stored, in the form of a content index database orotherwise, elsewhere in the information management system 100 (e.g., inthe primary storage devices 104, or in the secondary storage device108). Such index data provides the storage manager 140 or anothercomponent with an efficient mechanism for locating primary data 112and/or secondary copies 116 of data objects that match particularcriteria.

For instance, search criteria can be specified by a user through userinterface 158 of the storage manager 140. In some cases, the informationmanagement system 100 analyzes data and/or metadata in secondary copies116 to create an “off-line” content index, without significantlyimpacting the performance of the client computing devices 102. Dependingon the embodiment, the system can also implement “on-line” contentindexing, e.g., of primary data 112. Examples of compatible contentindexing techniques are provided in U.S. Pat. No. 8,170,995, which isincorporated by reference herein.

Classification Operations—Metabase

In order to help leverage the data stored in the information managementsystem 100, one or more components can be configured to scan data and/orassociated metadata for classification purposes to populate a metabaseof information. Such scanned, classified data and/or metadata may beincluded in a separate database and/or on a separate storage device fromprimary data 112 (and/or secondary copies 116), such that metabaserelated operations do not significantly impact performance on othercomponents in the information management system 100.

In other cases, the metabase(s) may be stored along with primary data112 and/or secondary copies 116. Files or other data objects can beassociated with user-specified identifiers (e.g., tag entries) in themedia agent 144 (or other indices) to facilitate searches of stored dataobjects. Among a number of other benefits, the metabase can also allowefficient, automatic identification of files or other data objects toassociate with secondary copy or other information management operations(e.g., in lieu of scanning an entire file system). Examples ofcompatible metabases and data classification operations are provided inU.S. Pat. Nos. 8,229,954 and 7,747,579, which are incorporated byreference herein.

Encryption Operations

The information management system 100 in some cases is configured toprocess data (e.g., files or other data objects, secondary copies 116,etc.), according to an appropriate encryption algorithm (e.g., Blowfish,Advanced Encryption Standard [AES], Triple Data Encryption Standard[3-DES], etc.) to limit access and provide data security in theinformation management system 100.

The information management system 100 in some cases encrypts the data atthe client level, such that the client computing devices 102 (e.g., thedata agents 142) encrypt the data prior to forwarding the data to othercomponents, e.g., before sending the data media agents 144 during asecondary copy operation. In such cases, the client computing device 102may maintain or have access to an encryption key or passphrase fordecrypting the data upon restore. Encryption can also occur whencreating copies of secondary copies, e.g., when creating auxiliarycopies. In yet further embodiments, the secondary storage devices 108can implement built-in, high performance hardware encryption.

Management Operations

Certain embodiments leverage the integrated, ubiquitous nature of theinformation management system 100 to provide useful system-widemanagement functions. As two non-limiting examples, the informationmanagement system 100 can be configured to implement operationsmanagement and e-discovery functions.

Operations management can generally include monitoring and managing thehealth and performance of information management system 100 by, withoutlimitation, performing error tracking, generating granularstorage/performance metrics (e.g., job success/failure information,deduplication efficiency, etc.), generating storage modeling and costinginformation, and the like.

Such information can be provided to users via the user interface 158 ina single, integrated view. For instance, the integrated user interface158 can include an option to show a “virtual view” of the system thatgraphically depicts the various components in the system usingappropriate icons. The operations management functionality canfacilitate planning and decision-making. For example, in someembodiments, a user may view the status of some or all jobs as well asthe status of each component of the information management system 100.Users may then plan and make decisions based on this data. For instance,a user may view high-level information regarding storage operations forthe information management system 100, such as job status, componentstatus, resource status (e.g., network pathways, etc.), and otherinformation. The user may also drill down or use other means to obtainmore detailed information regarding a particular component, job, or thelike.

In some cases the information management system 100 alerts a user suchas a system administrator when a particular resource is unavailable orcongested. For example, a particular primary storage device 104 orsecondary storage device 108 might be full or require additionalcapacity. Or a component may be unavailable due to hardware failure,software problems, or other reasons. In response, the informationmanagement system 100 may suggest solutions to such problems when theyoccur (or provide a warning prior to occurrence). For example, thestorage manager 140 may alert the user that a secondary storage device108 is full or otherwise congested. The storage manager 140 may thensuggest, based on job and data storage information contained in itsdatabase 146, an alternate secondary storage device 108.

Other types of corrective actions may include suggesting an alternatedata path to a particular primary or secondary storage device 104, 108,or dividing data to be stored among various available primary orsecondary storage devices 104, 108 as a load balancing measure or tootherwise optimize storage or retrieval time. Such suggestions orcorrective actions may be performed automatically, if desired. Furtherexamples of some compatible operations management techniques and ofinterfaces providing an integrated view of an information managementsystem are provided in U.S. Pat. No. 7,343,453, which is incorporated byreference herein. In some embodiments, the storage manager 140implements the operations management functions described herein.

The information management system 100 can also be configured to performsystem-wide e-discovery operations in some embodiments. In general,e-discovery operations provide a unified collection and searchcapability for data in the system, such as data stored in the secondarystorage devices 108 (e.g., backups, archives, or other secondary copies116). For example, the information management system 100 may constructand maintain a virtual repository for data stored in the informationmanagement system 100 that is integrated across source applications 110,different storage device types, etc. According to some embodiments,e-discovery utilizes other techniques described herein, such as dataclassification and/or content indexing.

Information Management Policies

As indicated previously, an information management policy 148 caninclude a data structure or other information source that specifies aset of parameters (e.g., criteria and rules) associated with secondarycopy or other information management operations.

One type of information management policy 148 is a storage policy.According to certain embodiments, a storage policy generally comprises alogical container that defines (or includes information sufficient todetermine) one or more of the following items: (1) what data will beassociated with the storage policy; (2) a destination to which the datawill be stored; (3) datapath information specifying how the data will becommunicated to the destination; (4) the type of storage operation to beperformed; and (5) retention information specifying how long the datawill be retained at the destination.

Data associated with a storage policy can be logically organized intogroups, which can be referred to as “sub-clients”. A sub-client mayrepresent static or dynamic associations of portions of a data volume.Sub-clients may represent mutually exclusive portions. Thus, in certainembodiments, a portion of data may be given a label and the associationis stored as a static entity in an index, database or other storagelocation.

Sub-clients may also be used as an effective administrative scheme oforganizing data according to data type, department within theenterprise, storage preferences, or the like. Depending on theconfiguration, sub-clients can correspond to files, folders, virtualmachines, databases, etc. In one exemplary scenario, an administratormay find it preferable to separate e-mail data from financial data usingtwo different sub-clients.

A storage policy can define where data is stored by specifying a targetor destination storage device (or group of storage devices). Forinstance, where the secondary storage device 108 includes a group ofdisk libraries, the storage policy may specify a particular disk libraryfor storing the sub-clients associated with the policy. As anotherexample, where the secondary storage devices 108 include one or moretape libraries, the storage policy may specify a particular tape libraryfor storing the sub-clients associated with the storage policy, and mayalso specify a drive pool and a tape pool defining a group of tapedrives and a group of tapes, respectively, for use in storing thesub-client data.

Datapath information can also be included in the storage policy. Forinstance, the storage policy may specify network pathways and componentsto utilize when moving the data to the destination storage device(s). Insome embodiments, the storage policy specifies one or more media agents144 for conveying data (e.g., one or more sub-clients) associated withthe storage policy between the source (e.g., one or more host clientcomputing devices 102) and destination (e.g., a particular targetsecondary storage device 108).

A storage policy can also specify the type(s) of operations associatedwith the storage policy, such as a backup, archive, snapshot, auxiliarycopy, or the like. Retention information can specify how long the datawill be kept, depending on organizational needs (e.g., a number of days,months, years, etc.)

The information management policies 148 may also include one or morescheduling policies specifying when and how often to perform operations.Scheduling information may specify with what frequency (e.g., hourly,weekly, daily, event-based, etc.) or under what triggering conditionssecondary copy or other information management operations will takeplace. Scheduling policies in some cases are associated with particularcomponents, such as particular sub-clients, client computing device 102,and the like. In one configuration, a separate scheduling policy ismaintained for particular sub-clients on a client computing device 102.The scheduling policy specifies that those sub-clients are to be movedto secondary storage devices 108 every hour according to storagepolicies associated with the respective sub-clients.

When adding a new client computing device 102, administrators canmanually configure information management policies 148 and/or othersettings, e.g., via the user interface 158. However, this can be aninvolved process resulting in delays, and it may be desirable to begindata protecting operations quickly.

Thus, in some embodiments, the information management system 100automatically applies a default configuration to client computing device102. As one example, when a data agent(s) 142 is installed on a clientcomputing devices 102, the installation script may register the clientcomputing device 102 with the storage manager 140, which in turn appliesthe default configuration to the new client computing device 102. Inthis manner, data protection operations can begin substantiallyimmediately. The default configuration can include a default storagepolicy, for example, and can specify any appropriate informationsufficient to begin data protection operations. This can include a typeof data protection operation, scheduling information, a target secondarystorage device 108, data path information (e.g., a particular mediaagent 144), and the like.

Other types of information management policies 148 are possible. Forinstance, the information management policies 148 can also include oneor more audit or security policies. An audit policy is a set ofpreferences, rules and/or criteria that protect sensitive data in theinformation management system 100. For example, an audit policy maydefine “sensitive objects” as files or objects that contain particularkeywords (e.g. “confidential,” or “privileged”) and/or are associatedwith particular keywords (e.g., in metadata) or particular flags (e.g.,in metadata identifying a document or email as personal, confidential,etc.).

An audit policy may further specify rules for handling sensitiveobjects. As an example, an audit policy may require that a reviewerapprove the transfer of any sensitive objects to a cloud storage site,and that if approval is denied for a particular sensitive object, thesensitive object should be transferred to a local storage device 104instead. To facilitate this approval, the audit policy may furtherspecify how a secondary storage computing device 106 or other systemcomponent should notify a reviewer that a sensitive object is slated fortransfer.

In some implementations, the information management policies 148 mayinclude one or more provisioning policies. A provisioning policy caninclude a set of preferences, priorities, rules, and/or criteria thatspecify how clients 102 (or groups thereof) may utilize systemresources, such as available storage on cloud storage and/or networkbandwidth. A provisioning policy specifies, for example, data quotas forparticular client computing devices 102 (e.g. a number of gigabytes thatcan be stored monthly, quarterly or annually). The storage manager 140or other components may enforce the provisioning policy. For instance,the media agents 144 may enforce the policy when transferring data tosecondary storage devices 108. If a client computing device 102 exceedsa quota, a budget for the client computing device 102 (or associateddepartment) is adjusted accordingly or an alert may trigger.

While the above types of information management policies 148 have beendescribed as separate policies, one or more of these can be generallycombined into a single information management policy 148. For instance,a storage policy may also include or otherwise be associated with one ormore scheduling, audit, or provisioning policies. Moreover, whilestorage policies are typically associated with moving and storing data,other policies may be associated with other types of informationmanagement operations. The following is a non-exhaustive list of itemsthe information management policies 148 may specify:

-   -   schedules or other timing information, e.g., specifying when        and/or how often to perform information management operations;    -   the type of secondary copy 116 and/or secondary copy format        (e.g., snapshot, backup, archive, HSM, etc.);    -   a location or a class or quality of storage for storing        secondary copies 116 (e.g., one or more particular secondary        storage devices 108);    -   preferences regarding whether and how to encrypt, compress,        deduplicate, or otherwise modify or transform secondary copies        116;    -   which system components and/or network pathways (e.g., preferred        media agents 144) should be used to perform secondary storage        operations;    -   resource allocation between different computing devices or other        system components used in performing information management        operations (e.g., bandwidth allocation, available storage        capacity, etc.);    -   whether and how to synchronize or otherwise distribute files or        other data objects across multiple computing devices or hosted        services; and    -   retention information specifying the length of time primary data        112 and/or secondary copies 116 should be retained, e.g., in a        particular class or tier of storage devices, or within the        information management system 100.

Policies can additionally specify or depend on a variety of historicalor current criteria that may be used to determine which rules to applyto a particular data object, system component, or information managementoperation, such as:

-   -   frequency with which primary data 112 or a secondary copy 116 of        a data object or metadata has been or is predicted to be used,        accessed, or modified;    -   time-related factors (e.g., aging information such as time since        the creation or modification of a data object);    -   deduplication information (e.g., hashes, data blocks,        deduplication block size, deduplication efficiency or other        metrics);    -   an estimated or historic usage or cost associated with different        components (e.g., with secondary storage devices 108);    -   the identity of users, applications 110, client computing        devices 102 and/or other computing devices that created,        accessed, modified, or otherwise utilized primary data 112 or        secondary copies 116;    -   a relative sensitivity (e.g., confidentiality) of a data object,        e.g., as determined by its content and/or metadata;    -   the current or historical storage capacity of various storage        devices;    -   the current or historical network capacity of network pathways        connecting various components within the storage operation cell;    -   access control lists or other security information; and    -   the content of a particular data object (e.g., its textual        content) or of metadata associated with the data object.

Exemplary Storage Policy and Secondary Storage Operations

FIG. 1E shows a data flow data diagram depicting performance of storageoperations by an embodiment of an information management system 100,according to an exemplary data storage policy 148A. The informationmanagement system 100 includes a storage manger 140, a client computingdevice 102 having a file system data agent 142A and an email data agent142B residing thereon, a primary storage device 104, two media agents144A, 144B, and two secondary storage devices 108A, 108B: a disk library108A and a tape library 108B. As shown, the primary storage device 104includes primary data 112A, 112B associated with a file systemsub-client and an email sub-client, respectively.

As indicated by the dashed box, the second media agent 144B and the tapelibrary 108B are “off-site”, and may therefore be remotely located fromthe other components in the information management system 100 (e.g., ina different city, office building, etc.). In this manner, informationstored on the tape library 108B may provide protection in the event of adisaster or other failure.

The file system sub-client and its associated primary data 112A incertain embodiments generally comprise information generated by the filesystem and/or operating system of the client computing device 102, andcan include, for example, file system data (e.g., regular files, filetables, mount points, etc.), operating system data (e.g., registries,event logs, etc.), and the like. The e-mail sub-client, on the otherhand, and its associated primary data 112B, include data generated by ane-mail client application operating on the client computing device 102,and can include mailbox information, folder information, emails,attachments, associated database information, and the like. As describedabove, the sub-clients can be logical containers, and the data includedin the corresponding primary data 112A, 112B may or may not be storedcontiguously.

The exemplary storage policy 148A includes a backup copy rule set 160, adisaster recovery copy rule set 162, and a compliance copy rule set 164.The backup copy rule set 160 specifies that it is associated with a filesystem sub-client 166 and an email sub-client 168. Each of thesesub-clients 166, 168 are associated with the particular client computingdevice 102. The backup copy rule set 160 further specifies that thebackup operation will be written to the disk library 108A, anddesignates a particular media agent 144A to convey the data to the disklibrary 108A. Finally, the backup copy rule set 160 specifies thatbackup copies created according to the rule set 160 are scheduled to begenerated on an hourly basis and to be retained for 30 days. In someother embodiments, scheduling information is not included in the storagepolicy 148A, and is instead specified by a separate scheduling policy.

The disaster recovery copy rule set 162 is associated with the same twosub-clients 166, 168. However, the disaster recovery copy rule set 162is associated with the tape library 108B, unlike the backup copy ruleset 160. Moreover, the disaster recovery copy rule set 162 specifiesthat a different media agent 144B than the media agent 144A associatedwith the backup copy rule set 160 will be used to convey the data to thetape library 108B. As indicated, disaster recovery copies createdaccording to the rule set 162 will be retained for 60 days, and will begenerated on a daily basis. Disaster recovery copies generated accordingto the disaster recovery copy rule set 162 can provide protection in theevent of a disaster or other data-loss event that would affect thebackup copy 116A maintained on the disk library 108A.

The compliance copy rule set 164 is only associated with the emailsub-client 166, and not the file system sub-client 168. Compliancecopies generated according to the compliance copy rule set 164 willtherefore not include primary data 112A from the file system sub-client166. For instance, the organization may be under an obligation to storemaintain copies of email data for a particular period of time (e.g., 10years) to comply with state or federal regulations, while similarregulations do not apply to the file system data. The compliance copyrule set 164 is associated with the same tape library 108B and mediaagent 144B as the disaster recovery copy rule set 162, although adifferent storage device or media agent could be used in otherembodiments. Finally, the compliance copy rule set 164 specifies thatcopies generated under the compliance copy rule set 164 will be retainedfor 10 years, and will be generated on a quarterly basis.

At step 1, the storage manager 140 initiates a backup operationaccording to the backup copy rule set 160. For instance, a schedulingservice running on the storage manager 140 accesses schedulinginformation from the backup copy rule set 160 or a separate schedulingpolicy associated with the client computing device 102, and initiates abackup copy operation on an hourly basis. Thus, at the scheduled timeslot the storage manager 140 sends instructions to the client computingdevice 102 to begin the backup operation.

At step 2, the file system data agent 142A and the email data agent 142Bresiding on the client computing device 102 respond to the instructionsreceived from the storage manager 140 by accessing and processing theprimary data 112A, 112B involved in the copy operation from the primarystorage device 104. Because the operation is a backup copy operation,the data agent(s) 142A, 142B may format the data into a backup format orotherwise process the data.

At step 3, the client computing device 102 communicates the retrieved,processed data to the first media agent 144A, as directed by the storagemanager 140, according to the backup copy rule set 160. In some otherembodiments, the information management system 100 may implement aload-balancing, availability-based, or other appropriate algorithm toselect from the available set of media agents 144A, 144B. Regardless ofthe manner the media agent 144A is selected, the storage manager 140 mayfurther keep a record in the storage manager database 140 of theassociation between the selected media agent 144A and the clientcomputing device 102 and/or between the selected media agent 144A andthe backup copy 116A.

The target media agent 144A receives the data from the client computingdevice 102, and at step 4 conveys the data to the disk library 108A tocreate the backup copy 116A, again at the direction of the storagemanager 140 and according to the backup copy rule set 160. The secondarystorage device 108A can be selected in other ways. For instance, themedia agent 144A may have a dedicated association with a particularsecondary storage device(s), or the storage manager 140 or media agent144A may select from a plurality of secondary storage devices, e.g.,according to availability, using one of the techniques described in U.S.Pat. No. 7,246,207, which is incorporated by reference herein.

The media agent 144A can also update its index 153 to include dataand/or metadata related to the backup copy 116A, such as informationindicating where the backup copy 116A resides on the disk library 108A,data and metadata for cache retrieval, etc. After the 30 day retentionperiod expires, the storage manager 140 instructs the media agent 144Ato delete the backup copy 116A from the disk library 108A.

At step 5, the storage manager 140 initiates the creation of a disasterrecovery copy 116B according to the disaster recovery copy rule set 162.For instance, at step 6, based on instructions received from the storagemanager 140 at step 5, the specified media agent 144B retrieves the mostrecent backup copy 116A from the disk library 108A.

At step 7, again at the direction of the storage manager 140 and asspecified in the disaster recovery copy rule set 162, the media agent144B uses the retrieved data to create a disaster recovery copy 116B onthe tape library 108B. In some cases, the disaster recovery copy 116B isa direct, mirror copy of the backup copy 116A, and remains in the backupformat. In other embodiments, the disaster recovery copy 116C may begenerated in some other manner, such as by using the primary data 112A,112B from the storage device 104 as source data. The disaster recoverycopy operation is initiated once a day and the disaster recovery copies116A are deleted after 60 days.

At step 8, the storage manager 140 initiates the creation of acompliance copy 116C, according to the compliance copy rule set 164. Forinstance, the storage manager 140 instructs the media agent 144B tocreate the compliance copy 116C on the tape library 108B at step 9, asspecified in the compliance copy rule set 164. In the example, thecompliance copy 116C is generated using the disaster recovery copy 116B.In other embodiments, the compliance copy 116C is instead generatedusing either the primary data 112B corresponding to the email sub-clientor using the backup copy 116A from the disk library 108A as source data.As specified, compliance copies 116C are created quarterly, and aredeleted after ten years.

While not shown in FIG. 1E, at some later point in time, a restoreoperation can be initiated involving one or more of the secondary copies116A, 116B, 116C. As one example, a user may manually initiate a restoreof the backup copy 116A by interacting with the user interface 158 ofthe storage manager 140. The storage manager 140 then accesses data inits index 150 (and/or the respective storage policy 148A) associatedwith the selected backup copy 116A to identify the appropriate mediaagent 144A and/or secondary storage device 116A.

In other cases, a media agent may be selected for use in the restoreoperation based on a load balancing algorithm, an availability basedalgorithm, or other criteria. The selected media agent 144A retrievesthe data from the disk library 108A. For instance, the media agent 144Amay access its index 153 to identify a location of the backup copy 116Aon the disk library 108A, or may access location information residing onthe disk 108A itself.

When the backup copy 116A was recently created or accessed, the mediaagent 144A accesses a cached version of the backup copy 116A residing inthe media agent index 153, without having to access the disk library108A for some or all of the data. Once it has retrieved the backup copy116A, the media agent 144A communicates the data to the source clientcomputing device 102. Upon receipt, the file system data agent 142A andthe email data agent 142B may unpackage (e.g., restore from a backupformat to the native application format) the data in the backup copy116A and restore the unpackaged data to the primary storage device 104.

Exemplary Secondary Copy Formatting

The formatting and structure of secondary copies 116 can vary, dependingon the embodiment. In some cases, secondary copies 116 are formatted asa series of logical data units or “chunks” (e.g., 512 MB, 1 GB, 2 GB, 4GB, or 8 GB chunks). This can facilitate efficient communication andwriting to secondary storage devices 108, e.g., according to resourceavailability. For example, a single secondary copy 116 may be written ona chunk-by-chunk basis to a single secondary storage device 108 oracross multiple secondary storage devices 108. In some cases, users canselect different chunk sizes, e.g., to improve throughput to tapestorage devices.

Generally, each chunk can include a header and a payload. The payloadcan include files (or other data units) or subsets thereof included inthe chunk, whereas the chunk header generally includes metadata relatingto the chunk, some or all of which may be derived from the payload. Forexample, during a secondary copy operation, the media agent 144, storagemanager 140, or other component may divide the associated files intochunks and generate headers for each chunk by processing the constituentfiles.

The headers can include a variety of information such as fileidentifier(s), volume(s), offset(s), or other information associatedwith the payload data items, a chunk sequence number, etc. Importantly,in addition to being stored with the secondary copy 116 on the secondarystorage device 108, the chunk headers can also be stored to the index153 of the associated media agent(s) 144 and/or the storage managerindex 150. This is useful in some cases for providing faster processingof secondary copies 116 during restores or other operations. In somecases, once a chunk is successfully transferred to a secondary storagedevice 108, the secondary storage device 108 returns an indication ofreceipt, e.g., to the media agent 144 and/or storage manager 140, whichmay update their respective indexes 150, 153 accordingly.

During restore, chunks may be processed (e.g., by the media agent 144)according to the information in the chunk header to reassemble thefiles. Additional information relating to chunks can be found in U.S.Pat. No. 8,156,086, which is incorporated by reference herein.

System Overview

FIG. 2 illustrates a block diagram of an exemplary networked storagearchitecture compatible with embodiments described herein. The system200 is configured to perform storage operations on electronic data in acomputer network. As shown, the system includes a storage manager 210and one or more of the following: a client 220, a data agent 240, abackup module 250, a shared storage pool 260, a media agent 270, and astorage device 280. In addition, the storage system can also include oneor more index caches as part of the media agent 270 and/or the storagemanager 210. The index caches can indicate logical associations betweencomponents of the system, user preferences, management tasks, and otheruseful data, as described in greater detail in application Ser. No.10/818,749, now U.S. Pat. No. 7,246,207, issued Jul. 17, 2007, hereinincorporated by reference in its entirety.

As illustrated, the client computer 220 can be communicatively coupledwith an information store, and/or the storage manager 210. Theinformation store contains data associated with the client 220, whichcan include primary copies of production data generated by softwareapplications executing on the client 220. The client 220 can also be indirect communication with the media agent 270 and/or the storage device280. All components of the storage system 200 can be in directcommunication with each other or communicate indirectly via the client220, the storage manager 210, the media agent 270, or the like.

With further reference to FIG. 2, the client computer 220 (alsogenerally referred to as a client) contains data in the informationstore that can be backed up in and then restored from the storage device280. In an illustrative embodiment, the client 220 can correspond to awide variety of computing devices including personal computing devices,laptop computing devices, hand-held computing devices, terminalcomputing devices, mobile devices, wireless devices, various electronicdevices, appliances and the like. In an illustrative embodiment, theclient 220 includes necessary hardware and software components forestablishing communication with the other components of storage system200. For example, the client 220 can be equipped with networkingequipment and browser software applications that facilitatecommunication with the rest of the components from storage system 200.Although not illustrated in FIG. 2, each client 220 can also display auser interface. The user interface can include various menus and fieldsfor entering storage and restore options. The user interface can furtherpresent the results of any processing performed by the storage manager210 in an easy to understand format. For instance, the storage manager210 may host software that executes on the storage manager 210 andgenerates the user interface, and the user interface may be accessibleusing a display on a client 220 or other computing device forinteracting with the storage manager 210.

The client computing devices 220 are be remotely located from oneanother in certain embodiments. Moreover, some or all of the contributedstorage resources 280 associated with a particular client 220 may bephysically local to the client 220, or in some other cases, may beremotely located from the particular client 220. As one example, a firstclient computing device 220 (CLIENT 1) may correspond to a desktopcomputer of a first user that is located at the user's home, along withassociated contributed storage devices 280. A second client computingdevice 2 (CLIENT 2) may correspond to a laptop computer of a seconduser, and the physical location of the laptop may change depending onuser's travel habits. In one embodiment, while the location of theclient computing device 220 of the second user may change, thecontributed storage devices 280 associated with the second user, on theother hand, may reside in a permanent location, e.g., at the user'shome. In other cases, the location of the contributed storage devices280 may also change.

In certain embodiments, each client computing device 220 and the storagedevice(s) 280, data agent(s) 240 and media agent(s) 270 associatedtherewith are associated with a particular user. Moreover, one or moreof the components associated with a particular user may be incommunication with one another over a relatively faster, lower latencyconnection than the connection between different clients 220 or betweencomponents associated with different clients 220. For instance,referring to FIG. 2, in one embodiment, CLIENT 1, CLIENT 2, CLIENT N−1and CLIENT N may be in communication with one another via a wide areanetwork (WAN), such as the Internet. On the other hand, componentsassociated with each respective client 220 communicate with one anotherover a lower latency connection, such as a local area network (LAN), aninternal system bus, combinations of the same or the like, depending onthe configuration. For instance, CLIENTS 1, 2 and N having media agents270 residing thereon may communicate with their corresponding mediaagents 270 via an internal bus. The media agent 270 associated withCLIENT N−1, on the other hand, may reside on a separate computingdevice, and CLIENT N−1 and its associated media agent 270 may thereforecommunicate over a LAN, some other network connection, or an externalbus interface such as a Universal Serial Bus (USB) interface.

Data agent 240 may be the same or similar to the data agents 142described with respect to FIGS. 1C-1E, and may be a software module thatis generally responsible for archiving, migrating, and recovering dataof a client computer 220 stored in an information store or other memorylocation. Each client computer 220 can have at least one data agent 240and the storage system 200 can support many client computers 220. Thestorage system 200 provides a plurality of data agents 240 each of whichis intended to backup, migrate, and recover data associated with adifferent application. For example, different individual data agents 240may be designed to handle Microsoft Exchange™ data, Microsoft Windowsfile system data, and other types of data known in the art. If a clientcomputer 220 has two or more types of data, one data agent 240 may beimplemented for each data type to archive, migrate, and restore theclient computer 220 data.

A shared storage pool 260 generally includes one or more clients 220that contribute storage resources to the pool, and that are thusaccessible for data storage operations involving source data generatedby the other clients 220. Thus, some or all of the space in the storagedevices 280 associated with the clients 220 in the shared storage pool260 may be available to other clients 220 in the storage pool 260 forsecondary storage operations, such as, without limitation, backup,archive or snapshot operations. FIG. 2 illustrates n number of clients220. Each client 220 may have one or more associated storage devices280. For example, clients 1 and 2 each have one storage device 280, andclient n−1 has two storage devices 280. Each client 220 may have atleast one data agent 240 and at least one media agent 270 installedthereon. While the data agent 240 and media agent 270 are shown asresiding on the clients 220, the data agent 240 and/or media agent 270may instead reside on a separate computing device from the client 220.As indicated previously, data in some cases is be sent directly betweenthe clients 220 without passing through the storage manager 210. Thiscan help avoid a communication bottleneck and can therefore help improvethroughput. This arrangement may also be advantageous for security andprivacy reasons, as it may be desirable for the users of the clientcomputers 220 to avoid having their data made accessible by the storagemanager 210. In one alternative embodiment, the at least some datapasses through the storage manager 210 on the path from a source clientto a target client during a storage operation.

In some embodiments, the share list 290 for a client defines the storageresources in the pool available to that client for data storageoperations, such as secondary copy operations (e.g., backups, archivesor snapshots). Thus, whether a client 220 can utilize the storageresources of another client 220 may be determined based on a share list290 for the client 220. For example, the share list for client 1includes clients n−1 and n. Client 1 may back up its data to client n−1and/or client n, but client 1 may not back up its data to client 2. Oncethe data is successfully backed up to another client 220, the clientthat requested backup may restore its data from the client(s) 220 whereits data is stored. The data may be stored on the client 220 machine(e.g., on a hard drive or other storage device within a laptop or othercomputing device) or storage device(s) 280 associated with that client220. The shared storage pool 260 will be discussed in more detail withrespect to FIGS. 3-7.

A backup module 250 generally manages storage operations (e.g., backupsor other secondary copy operations) among the clients 220 in the sharedstorage pool 260. The backup module 250 may create and maintain theshare list 290 for the clients 220. The backup module 250 may determineparameters relating to backup and send them to clients 220 requestingbackup. The parameters relating to storage operation, such asidentifier(s) indicating the storage resources involved in the storageoperation (e.g., a backup operation), and the like, may be determinedbased on the share list 290 and/or the client configuration information291. The backup module 250 also may keep track of information regardingthe storage operations, which may be in the form of an index 292 ofjobs. In response to restore requests from clients 220, the backupmodule 250 may determine and send parameters relating to restore to therequesting clients 220. The backup module 250 may communicate with theclients 220 within the storage pool 260 via a network. In someembodiments, the backup module 250 is a software module that forms apart of or resides on the storage manager 210 or, alternatively, themedia agents 270. The backup module 250 can additionally be a softwaremodule executing on one or more of the client computers 220. In someembodiments, the backup module 250 may be implemented as a part of thedata agent 240. The backup module 250 will be discussed in more detailwith respect to FIGS. 3-7.

Generally speaking, storage manager 210 may be the same or similar tothe storage managers 140 described with respect to FIGS. 1C-1E, and canbe software module or application that coordinates and controls thesystem. The storage manager 210 communicates with all elements of thestorage system 200 including the client computers 220, data agents 240,the media agents 270, and the storage devices 280, to initiate andmanage system backups, migrations, recoveries, and the like. The storagemanager 210 can be located within the client 220, the media agent 270,or can be a software module within a separate computing device. In otherwords, the media agent 270 and/or the client 220 can include a storagemanager module. In one embodiment, the storage manager 210 is located inclose proximity to the client 220 and communicates with the client 220via a LAN. In another embodiment, the storage manager 210 communicateswith the client 220 via a WAN. Similarly, in one embodiment, the storagemanager 210 communicates with the media agent 270 via a LAN, and inanother embodiment communicates with the media agent 270 via a WAN.

The storage manager 210 can also deduplicate the data that is beingbacked up in storage device 280. For example, the storage manager 210can analyze individual data blocks being backed up, and replaceduplicate data blocks with pointers to other data blocks already storedin the storage device 280. To identify duplicate data blocks, thestorage manager 210 can perform hash functions, on each data block. Thehash functions of the different data blocks can be compared. Matchinghashes of different data blocks can indicate duplicate data, which canbe replaced with a pointer to previously stored data. Additional detailregarding deduplicating data is provided in the applicationsincorporated by reference herein. Other components of storage system 200can perform the deduplication techniques on the data blocks, such as themedia agent 270, the client 220, and/or the storage device 280.

A media agent 270 may be the same or similar to the media agents 144described with respect to FIGS. 1C-1E. The media agent 270 is generallya software module that conducts data, as directed by the storage manager210, between locations in the storage system 200. For example, the mediaagent 270 may conduct data between the client computer 220 and one ormore storage devices 280, between two or more storage devices 280, etc.Although not shown in FIG. 2, one or more of the media agents 270 canalso be communicatively coupled to one another. In some embodiments, themedia agent 270 communicates with the storage manager 210 via a LAN orSAN. In other embodiments, the media agent 270 communicates with thestorage manager 210 via a WAN. The media agent 270 generallycommunicates with the storage devices 280 via a local bus. In someembodiments, the storage device 280 is communicatively coupled to themedia agent(s) 270 via a Storage Area Network (“SAN”).

The storage devices 280 can include a tape library, a magnetic mediastorage device, an optical media storage device, or other storagedevice. The storage devices 280 can further store the data according toa deduplication schema as discussed above. The storage devices 280 canalso include a signature block corresponding to each stored data block.

Further embodiments of storage systems such as the one shown in FIG. 2are described in application Ser. No. 10/818,749, now U.S. Pat. No.7,246,207, issued Jul. 17, 2007, which is hereby incorporated byreference in its entirety. In various embodiments, components of thestorage system may be distributed amongst multiple computers, or one ormore of the components may reside and execute on the same computer.

Furthermore, components of the storage system of FIG. 2 can alsocommunicate with each other via a computer network. For example, thenetwork may comprise a public network such as the Internet, virtualprivate network (VPN), token ring or TCP/IP based network, wide areanetwork (WAN), local area network (LAN), an intranet network,point-to-point link, a wireless network, cellular network, wireless datatransmission system, two-way cable system, interactive kiosk network,satellite network, broadband network, baseband network, combinations ofthe same or the like.

Additionally, the various components of FIG. 2 may be configured fordeduplication. For example, one or more of the clients 220 can include adeduplicated database (DDB). The data stored in the storage devices 280may also be deduplicated. For example, one or more of the media agents270 associated with the respective storage devices 280 can manage thededuplication of data in the storage devices 280.

An Example Data Storage System for Backup Using Social Networking

FIG. 3 is a data flow diagram illustrative of the interaction betweenthe various components of an example data storage system 300 configuredto implement backup using a shared, on-line pool of data storageresources according to certain embodiments. As illustrated, the examplestorage system 300 includes a storage manager 310, one or more clients320, one or more data agents 340, a backup module 350, a shared storagepool 360, one or more media agents 370, and one or more storage devices380. The storage manager 310, the client 320, the data agent 340, thebackup module 350, the storage pool 360, the media agent 370, and thestorage device 380 can be similar or the same as the storage manager210, the client 220, the data agent 240, the backup module 250, thestorage pool 260, the media agent 270, and the storage device 280 inFIG. 2. Although not shown, there may be a different information storeassociated with each of the clients 320. The system 300 may include oneor more of each component. All components of the system 300 can be indirect communication with each other or communicate indirectly via theclient 320, the storage manager 310, the media agent 370, or the like.In certain embodiments, some of the components in FIG. 3 shown asseparate components can reside on a single computing device. Forexample, the backup module 350 can be on the storage manager 310 or on aseparate computing device.

With further reference to FIG. 3, the interaction between the variouscomponents of the example data storage system 300 configured toimplement data protection operations using a shared, on-line pool ofdata storage resources will now be described in greater detail withrespect to data flow steps indicated by the numbered arrows. Whiledescribed with respect to a backup copy operation to simplify thediscussion, other types of storage operations (e.g., archive operations,snapshot operations, etc.) are also compatible. For illustrationpurposes, a client 320 requesting backup may be referred to as“requesting client,” and a client 320 where data is backed up may bereferred to as “backup client.” Moreover, where data is referred to asbeing backed up to a client, this can refer to the data being stored inthe storage device(s) 380 associated with that client.

At data flow step 1, a user associated with a client 320 joins theshared storage pool 360, for example, by registering with or signing upwith the storage manager 310 (e.g., via a web interface or a portal).For instance, the storage manager may create and maintain an accountassociated with the user. When joining the storage pool 360, a userassociated with the client 320 may enter information for a share list390 associated with the client 320. A share list 390 may identify one ormore clients 320 that are known to or otherwise associated with theclient 320. The clients 320 included in the share list 390 may serve ascandidates for backup location. The backup module 350 may maintain theshare list 390 for each client 320 in the storage pool 360. The backupmodule 350 may create the share list 390 for the client 320 joining thestorage pool 360 and store the information entered by the client 320 inthe share list 390. The backup module 350 may also add informationregarding the client 320 to the client configuration information 391.The client configuration information 391 will be explained in moredetail with respect to data flow step 3. Upon joining the storage pool360, the user may install the data agent 340 and the media agent 370.The data agent 340 and the media agent 370 may be downloaded from a userinterface (UI) provided by the storage manager 310.

In a specific example relating to FIG. 3, Client A joins the storagepool 360 by sending a request to the storage manager 310. When joiningthe storage pool 360, the user associated with Client A may be asked toenter information for its share list 390. Such information can includeclients 320 associated with Client A. The user associated with Client Aindicates Clients B and C as the clients 320 to be added to itsassociated share list 390. The backup module 350 creates a share list390 for Client A and adds Clients B and C to the share list 390.Alternatively, the storage manager 310 may provide a default share list390, e.g., if the user does not provide the information to add to theshare list 390 for the client 320. The storage manager 310 may alsoassign default friends for the share list 390 based on a number offactors. Such factors may include geographic proximity (e.g., time zone)and storage utilization. For example, the storage manager 310 may assignclients 320 and/or their associated storage devices 380 that haverelatively low storage utilization as compared to other clients 320and/or associated storage device 380 as default friends. The backupmodule 350 may also add information about Client A to the clientconfiguration information 391. The user for Client A then downloads andinstalls the data agent 340 and the media agent 370.

A user associated with a client 320 in the storage pool 360 maycontribute storage resources to the storage pool 360 in a number ofways. A user may provide storage space associated with storage deviceslocated within the user's client 320 machine (e.g., a laptop hard driveor solid state drive). Or a user may provide additional storage devices380 (e.g., external to the client 320), which can be accessed via theclient 320. Additional storage devices 380 may be easily added to thestorage pool 360 by installing a media agent 370 directly on the storagedevices 380 or on separate computing devices that are in communicationwith the storage devices 380. In some embodiments, a user may be allowedto use the same amount of storage resource as the amount the userprovides. In other embodiments, a user may contribute resources to thepool 360 without utilizing any storage. In certain embodiments, a usermay not contribute any storage and pay a fee to use storage from thepool 360. If a user contributes resources, the user may not pay any feesor pay a pro-rated fee based on the amount of resources the usercontributes.

At data flow step 2, the client 320 sends a request to the storagemanager 310 to perform a backup operation. After a client 320 joins thestorage pool 360, the client 320 may back up data to other clients 320on its share list 390. The client 320 may initiate backup by sending abackup request to the storage manager 310. Alternatively, the storagemanager 310 may initiate backup without a request from the client 320,e.g., according to a storage policy for the client 320. A userassociated with the client 320 may set up preferences and configurationsfor backup operations with the storage manager 310 (e.g., from thestorage manager 310 GUI), and the storage manager 310 may initiatebackup (or another type of secondary copy) according to the userconfigurations. For example, backup may occur according to a storagepolicy or a schedule. In some embodiments, the data agent 340 may send arequest for backup to the storage manager 310.

At data flow step 3, the backup module 350 consults the share list 390for the requesting client 320 in order to determine where data should bebacked up. As explained above, the share list 390 may include clients320 whose identities are known to the requesting client 320, or clients320 that are otherwise associated with the requesting client 320. Forexample, the share list 390 may be based on friends of a user in asocial networking website. In some embodiments, the share list 390 isbased on the Friends list in Facebook. In such embodiments, Client A maybe friends with Clients B and C on Facebook.

The backup module 350 may select a backup client 320 from the share list390 of the requesting client 320. In FIG. 3, the backup module 350 mayselect Client B or C (or both) as backup location(s) for Client A byreferring to the share list 390 for Client A. The backup module 350 mayalso refer to the client configuration information 391 in selecting thebackup client 320. The client configuration information 391 may includethe following information for some or all of the clients in the on-linestorage pool 360, without limitation: type of storage device associatedwith a client 320, type of processor or other hardware associated with aclient 320, type or number of data agent(s), media agent(s) or othersoftware components installed on or associated with a client 320, amountof storage resources contributed to the pool that is associated with theclient 320, user feedback, etc. Data can be backed up to the client 320machine itself (e.g., where the client machine is a laptop, to a harddrive of the laptop) or storage devices 380 associated with the client320 (e.g., external to the client 320). Thus, the client configurationinformation 391 may include information about the client 320 machine orthe storage devices 380 associated with the client 320. The datastructures for the client configuration information 391 will beexplained in more detail with respect to FIG. 5.

Data of a requesting client 320 can be backed up to a single client 320or may be distributed across multiple clients 320. Accordingly, thebackup module 350 may select one or more backup clients 320 from theshare list 390. For example, Client A can back up its data to onlyClient B or only Client C. Alternatively, Client A may back up itsentire data to both Clients B and C. Or Client A may back up a part ofits data to Client B and the rest of its data to Client C.

As explained above, the data of a requesting client 320 can be backed upto the client 320 machine (e.g., a laptop) and/or the storage devices380 provided by the client 320. As such, a client 320 can incorporateadditional storage devices 380 in order to increase space available forbackup. In some embodiments, a client 320 in the storage pool 360 mayact as a storage provider by providing a number of storage devices 380.A client 320 can install a media agent 370 either on the client 320 oron separate computing devices, and data to be backed up can be conductedvia the media agent 370 to the storage devices 380. The data may bebacked up to any combination of storage provided by the client 320machine and storage devices 380. For instance, the data may only bewritten to storage within the client machine 320, or only to a storagedevice 380, that may be external to but coupled to the client machine320. Or the data may be written to the client machine 320 and one ormore storage devices 380.

For example, a particular user associated with a particular client mayhave a relatively large number of “friends” on his or her share list390. The user may decide to purchase additional storage devices 380 sothat he or she can act as a storage provider to the large number offriends in the pool. The user may charge or otherwise be compensated foruse of his or her storage resources. For instance, the user may becompensated based on the amount of storage resources contributed to thepool and/or based on the utilization of that user's storage resources.Moreover, the entity that provides management and administrationservices for backup in the storage pool 360, e.g., the entity thatprovides the storage manager 310 and/or the backup module 350, may takea percentage of the fees in return for administering the pooled storagesystem.

In some embodiments, storage resources associated with a client 320 inthe shared storage pool 360 may include cloud storage and may, e.g., beprovided by a cloud vendor. In other embodiments, a client 320 may be adata center. In these embodiments, the requesting client 320 may havethe option to choose to back up to client(s) 320 on its share list 390or to back up to the cloud storage or the data center. Or, in somecases, the cloud storage or data center may be added to the share list390.

As discussed above, the backup module 350 can determine the backupclient(s) 320 for the requesting client 320 based on a number offactors, including the share list 390 for the requesting client 320 andthe client configuration information 391.

At data flow step 4, the backup module 350 sends information regardingparameters for the storage pool 360 to the requesting client 320. Theinformation sent to the requesting client 320 may include a list of oneor more backup clients 320, and type of storage and processor associatedwith these selected clients 320. In some embodiments, the requestingclient 320 may select a backup client 320 from a list of candidatebackup clients 320 based on the information sent by the backup module350. For example, Client A, the requesting client 320, may indicate inits backup request that it wants to back up its data across multipleclients 320. The backup module 350 may include Clients B and C as backupclients 320 in the information sent to Client A. However, Client A maydecide not to back up data to Client B if it does not find Client Badequate based on the type of storage and processor information. In someembodiments, the user may pre-configure preferences for parametersrelating to backup (e.g., using the storage manager 310 GUI), ratherthan doing it on a backup-by-backup basis.

The storage manager 310 may implement logic to determine which storagedevices to choose as backup clients 320. Such determination may be basedon a number of factors, such as amount of available storage capacity,availability of clients, utilization rate of contributed storageresources, user feedback, geographic proximity, etc. For instance, thestorage manager 310 may select clients 320 in the share list based onthe amount of available storage capacity provided by each client 320.The storage manager 310 may also select clients 320 in the share listbased on availability, where storage devices of friends who arecurrently or historically off-line (e.g., shut down their PC at night)are less likely to be selected than storage resources of friends who aregenerally available. The storage manager 310 may also select clients 320in the share list with relatively low utilization rates. Users mayprovide feedback regarding various clients 320, and the storage manager310 may select clients 320 based on the user-generated feedback andratings. The storage manager 310 may also select clients 320 based ongeographic location, e.g., a location farther than a certain distance. Auser may also choose a specific backup client 320, e.g., by overridingall the factors.

At data flow step 5, the requesting client 320 backs up data to one ormore backup clients 320. For example, the media agent 370 associatedwith the backup client 320 is assigned by the storage manager 310 toconvey the data to contributed storage resources associated with thebackup client 320. The storage resources can include one or more of thestorage devices 380, or a storage device residing on the client 320itself, such as an integrated hard drive or solid state drive. As anexample, where the backup client is CLIENT B, the media agent 370residing on CLIENT B may be assigned to convey the data to one or moreof the storage devices 380 associated with CLIENT B. While the mediaagent 370 associated with (e.g., residing on or local to) the backupclient 320 may be assigned to convey the backup data to the storagedevices 380 of the backup client 320 (or other storage resources of thebackup client 320), in some other embodiments, a different media agent370 in the pool 360 may be selected. For instance, where CLIENT B is thebackup client 320, the storage manager 310 may assign a media agent 370associated with CLIENT C (e.g., residing on or local to CLIENT C) toconvey the data to the appropriate contributed storage resourcesassociated with CLIENT B (e.g. the storage device(s) 380). Selection ofthe media agent 370 may be based on media agent availability, networkutilization or bandwidth, or some other appropriate criteria. When datais backed up to more than one client 320, backup to multiple clients 320may occur in parallel in order to reduce the amount of time for backup.Backup can occur according to a storage policy or a schedule. Forexample, backup at the requesting client 320 may be scheduled for everySunday at 2 am. Or in another example, the requesting client 320 may bea laptop, and backup may run every time the requesting client 320 isconnected to a power source. This type of backup may be referred to as“opportunistic scheduling.” Opportunistic scheduling may also depend onthe availability of the backup client 320. For example, the backupclient 320 may not be available at the time the requesting client 320requests backup (e.g., according to a schedule). In such case, thebackup module 350 or the requesting client 320 may monitor theavailability of the backup client 320 and initiate backup at a latertime when the backup client 320 becomes available. For example, Client Amay be scheduled to back up its data each night to Client B, which is alaptop. However, the user associated with Client B may often shut downthe laptop at night. The backup module 350 or Client A may monitor thestatus of Client B, and the backup can start when Client B is backonline.

Data to be backed up may be encrypted to protect the information. Datato be backed up can also be deduplicated to save storage space in thebackup client 320 and reduce backup time. The media agent 370 maydeduplicate the data to be backed up. Data to be backed up may be sentdirectly from the requesting client 320 to the backup client 320 withoutbeing sent through the storage manager 310 and/or the backup module 350.In this manner, the storage manager 310 and/or the backup module 350 mayact as an exchange or a broker for backup by connecting the requestingclient 320 and backup client(s) 320 without handling the data.

At data flow step 6, the backup client 320 sends a backup report to therequesting client 320 and/or the storage manager 310. For instance, oncethe backup completes or fails, the backup client 320 may send statusinformation relating to the backup to the requesting client 320. Statusinformation may indicate whether the backup was successful or not. Thebackup report may also be sent to the requesting client 320 at latertimes subsequent to the backup to inform the requesting client 320 thatthe data backed up on a specific date is available. For example, thebackup client 320 may send a verification report each day after thebackup to inform the requesting client 320 whether the backed up data isavailable for restore.

Same or similar information may also be sent to the storage manager 310.The storage manager 310 or the backup module 350 may maintain records ofthe backup operations so that when a client 320 requests restore of thebacked up data, the storage manager 310 or the backup module 350 canindicate where data may be restored from. Backup operations can bestored in an index 392 of backup jobs. The index 392 may also maintainrecords of restore jobs. The index 392 may include information like typeof job, requesting client, backup/restore location, status, etc. Thedata structures for the index 392 will be explained in more detail withrespect to FIG. 5.

As explained above, the backup module 350 provides management andadministration services relating to backup between clients 320 within ashared storage pool 360 and acts as an intermediary between the clients320 for backup. In this manner, the shared storage pool 360 providesreadily available storage to clients 320 in the pool, and from theperspective of the user associated with the individual clients, thebackup process is relatively streamlined since the backup module 350oversees the management of the backup/restore operations. In addition,because each user can enter the information for his or her share list390, users can control and know in advance the identities of clients 320where their data may be stored. Accordingly, a share list based storagepool can add an extra layer of security for protection of user data.

The shared storage pool 360 can include a variety of types of clients320. For instance, client computing machines 320 can include any type ofappropriate computing device including laptops, desktops, mobiledevices, etc., and the client devices 320 and/or associated storagedevices 380 may be located in user's residences, corporate offices, orany other suitable location. The example storage system 300 may also beused in an enterprise context. Clients 320 may be added to a sharedstorage pool 360, and data may be backed up to clients 320 within thepool 360. For instance, a corporation that has a headquarter located inNew York and a branch office located in Texas may decide to back up datagenerated by clients in the New York location to clients 320 in theTexas branch office, and/or vice versa. The clients 320 in New York andTexas may form part of a shared storage pool 360 for the corporation,for example. Such backup may be performed to comply with legalrequirements, e.g., a corporation may be required to keep copies of datain a geographically remote area from the headquarter location. A client320 within the enterprise shared storage pool 360 may also be a datacenter or cloud storage. A data center or cloud storage can easily beadded to the storage pool 360, for example, by installing the data agent340 and the media agent 370 on the client 320. The enterprise sharedstorage pool 360 may also operate based on share lists 390 for clients320.

FIG. 4 is a data flow diagram illustrative of the interaction betweenthe various components of an example data storage system 400 configuredto implement data protection operations using a shared, on-line pool ofdata storage resources according to certain embodiments. As illustrated,the example storage system 400 includes a storage manager 410, one ormore clients 420, one or more data agents 440, a backup module 450, astorage pool 460, one or more media agents 470, and one or more storagedevices 480. The storage manager 410, the client 420, the data agent440, the backup module 450, the storage pool 460, the media agent 470,and the storage device 480 can be similar or the same as the storagemanager 210, 310, the client 220, 320, the data agent 240, 340, thebackup module 250, 350, the storage pool 260, 360, the media agent 270,370, and the storage device 280, 380 in FIGS. 2 and 3. Although notshown, there may be a different information store associated with eachof the clients 420. The system 400 may include one or more of eachcomponent. All components of the system 400 can be in directcommunication with each other or communicate indirectly via the client420, the storage manager 410, the media agent 470, or the like. Incertain embodiments, some of the components in FIG. 4 shown as separatecomponents can reside on a single computing device. For example, thebackup module 450 can be on the storage manager 410 or on a separatecomputing device.

With further reference to FIG. 4, the interaction between the variouscomponents of the example data storage system 400 configured toimplement data protection operations using a shared, on-line pool ofdata storage resources will now be described in greater detail withrespect to data flow steps indicated by the numbered arrows. Whiledescribed with respect to restoring a backup copy operation to simplifythe discussion, the restore technique is also compatible with othertypes of secondary copies (e.g., archive copies, snapshot copies, etc.).For illustration purposes, a client 420 requesting restore may bereferred to as “requesting client,” and a client 420 where data isbacked up/restored from may be referred to as “backup client.” Moreover,where data is referred to as being backed up to a client, this can referto the data being stored in the storage device(s) 380 associated withthat client.

At data flow step 1, a user associated with a client 420 requestsrestore to the storage manager 410. After the data of the client 420 hasbeen backed up to one or more backup clients 420, the user may wish torestore the data from the backup client(s) 420. The user may initiaterestore by sending a restore request to the storage manager 410, e.g.,from the storage manager 410 GUI.

At data flow step 2, the backup module 450 sends information regardingparameters for the restore to the client 420. The backup module 450 mayrefer to the index 492 that stores data regarding backup and restorejobs to determine, for the particular backup job that is being restored,to which clients 420 the requesting client's 420 data has been backedup. The information sent to the requesting client 420 may include a listof one or more backup clients 420 storing the data of the requestingclient 420.

At data flow step 3, the requesting client 420 requests data from thebackup client 420. The requesting client 420 may send data requests toone or more backup clients 420 indicated in the parameters for restoresent by the backup module 450. For example, the data of the requestingclient 420 may have been backed up in a distributed manner over multiplebackup clients 420. In such case, the requesting client 420 may send adata request to each backup client 420. Restore from multiple clients420 may occur in parallel to reduce the amount of time for the restore.If the entire data of the requesting client 420 was backed up tomultiple backup clients 420, the backup module 450 may send informationfor all backup clients 420 that store the requesting client's 420 data.The requesting client 420 then can choose to restore from one of themultiple backup clients 420.

At data flow step 4, the requesting client 420 restores the data fromthe backup client 420. If the backup client 420 is available forrestore, the requesting client 420 restores its data from the backupclient 420. If the backup client 420 is unavailable for some reason, therequesting client 420 may send restore requests to other backup clients420, or wait and try restoring from this particular backup client 420 ata later time. If the requesting client's 420 data has been backed up tomultiple backup clients 420, the requesting client 420 may restore itsdata in a piecemeal fashion base on availability of the backup clients420. For example, Client A may restore a first portion of its data fromClient B at time T₁ and a second portion of its data from Client C attime T₂.

At data flow step 5, the backup client 420 sends a restore report to therequesting client 420 and/or the storage manager 410. Once the restorecompletes or fails, the backup client 420 may send status informationrelating to the restore to the storage manager 410. Status informationmay indicate whether the restore was successful or not. The restorereport may also be sent to the requesting client 420. The storagemanager 410 or the backup module 450 may maintain records of the restoreoperations, for example, to determine which clients 420 or storagedevices 480 often cause problems as the restore source. Restoreoperations can be stored in the index 492 of jobs, along with backupoperations. The index 492 may include information such as type of job,requesting client, backup/restore location, status, etc. The datastructures for the index 492 will be explained in more detail withrespect to FIG. 5.

FIG. 5 illustrates example data structures that can be used toadminister a shared, on-line pool of data storage resources to createand manage secondary copies of data, according to certain embodiments.The client configuration information data structure 591 can include dataabout each client 320 device and/or storage device(s) 380 associatedwith each client 320. For example, the client configuration datastructure 591 may contain the following information: client, storagedevice, available space, type of storage, type of processor,availability information, and user feedback and/or ratings. Client mayindicate the client 320 name; storage device may indicate the storagedevice 380 name. Type of storage may indicate information about themodel and manufacturer of the client 320 or the associated storagedevice(s) 380. Available space may be determined based on the type ofstorage information. For example, the backup module 350 can determinefrom the manufacturer and model information for a client 320 or astorage device 380 the total available storage provided by thatparticular device. Alternatively, the available space information may becollected from the clients 320 and may reflect available storage foreach client 320 at certain points in time. Availability information mayindicate the availability of a client 320 and/or a storage device 380.The availability information may include a current “live” statusindicating whether or not the client and/or resources are available atthat moment. The availability information may also be historical, basedon the availability over a certain period of time. User feedback and/orratings may include user opinion, comments, scores, etc. relating tovarious clients 320 and storage devices 380. User feedback may beindicated, e.g., by number of stars, by a numerical score, etc.

The index 592 can include data about backup and restore operationsbetween clients 320 in the storage pool 360. For example, the index 592may contain the following information: job ID, job type, client,location, and status. Job ID may be the ID for the backup or restoreoperation. Job type may indicate whether the operation is a backup or arestore. Client may indicate the name of the client 320 that requestedthe backup or the restore. Location may indicate the client 320 to whichdata is backed up or from which the data is restored. Status mayindicate whether the job was successful or not. Although not shown, theindex 592 may also include a date and time associated with the job. Forexample, the date for a backup job can allow the backup module 450 todetermine the most recent backup that is available for restore.

FIG. 6 is a flow diagram illustrative of one embodiment of a routine 600for utilizing a shared, on-line pool of data storage resources to createsecondary copies of data. The routine 600 is described with respect tothe system 300 of FIG. 3. However, one or more of the steps of routine600 may be implemented by other data storage systems, such as thosedescribed in greater detail above with reference to FIGS. 2 and 4. Theroutine 600 can be implemented by any one, or a combination of, aclient, a storage manager, a data agent, a backup module, a media agent,and the like. Moreover, further details regarding certain aspects of atleast some of steps of the routine 600 are described in greater detailabove with reference to FIG. 3. Although described in relation to backupoperations for the purposes of illustration, the process of FIG. 6 canbe compatible with other types of storage operations, such as, forexample, archiving, migration, snapshots, replication operations, andthe like.

At block 601, a user associated with a client 320 joins the storage pool360. The user may enter information for a share list 390 associated withthe client 320. The client 320 information may be added to the clientconfiguration information 391. The user may install the data agent 340and the media agent 370 on the client 320 or on separate computingdevices.

At block 602, the client 320 sends a request to back up its data to thestorage manager 310. The storage manager 310 or the backup module 350may consult the share list 390 for the requesting client 320 in order toprovide information regarding possible backup location(s). The backupmodule 350 may also refer to the client configuration information 391 toselect backup clients 320.

At block 603, the client 320 receives information regarding parametersfor the storage pool 360. The parameters for the storage pool 360 mayindicate where the client 320 can back up its data and may include alist of candidate backup clients 320.

At block 604, the client 320 backs up the data to one or more backupclients 320. The client 320 may select a backup client 320 from a listof clients 320 in the parameters. The client 320 may choose to back upto one, several, or all backup clients 320 in the list.

At block 605, the client 320 receives information regarding backupstate. The backup state information may be sent immediately after thebackup operation to indicate whether the backup operation wassuccessful. The backup state information may also be sent at a latertime, e.g., at a periodic interval, to indicate whether the data asbacked up on a particular date is still available for restore. Forexample, the backup client 320 may send verification information on adaily basis to notify the requesting client 320 that the data backed upas of mm-dd-yyyy is available.

The routine 600 can include fewer, more, or different blocks than thoseillustrated in FIG. 6 without departing from the spirit and scope of thedescription. Moreover, it will be appreciated by those skilled in theart and others that some or all of the functions described in thisdisclosure may be embodied in software executed by one or moreprocessors of the disclosed components and mobile communication devices.The software may be persistently stored in any type of non-volatilestorage.

FIG. 7 is a flow diagram illustrative of one embodiment of a routine 700for utilizing a shared, on-line pool of data storage resources to createsecondary copies of data. The routine 700 is described with respect tothe system 300 of FIG. 3. However, one or more of the steps of routine700 may be implemented by other data storage systems, such as thosedescribed in greater detail above with reference to FIGS. 2 and 4. Theroutine 700 can be implemented by any one, or a combination of, aclient, a storage manager, a data agent, a backup module, a media agent,and the like. Moreover, further details regarding certain aspects of atleast some of steps of the routine 700 are described in greater detailabove with reference to FIG. 3. Although described in relation to backupoperations for the purposes of illustration, the process of FIG. 7 canbe compatible with other types of storage operations, such as, forexample, archiving, migration, snapshots, replication operations, andthe like.

At block 701, a user associated with a client 320 sends a request torestore data to the storage manager 310. At block 702, the client 320receives information regarding parameters for restore from the storagemanager 310. The storage manager 310 or the backup module 350 mayconsult the index 392 of jobs to determine the restore location(s). Theparameters may include a list of backup clients 320 that store therequesting client's 320 data.

At block 703, the client 320 sends a restore request to backuplocation(s). The client 320 may send the restore request to multiplebackup clients 320, e.g., if its data is stored across more than oneclient 320 in a distributed manner. At block 704, the client 320restores the data from one or more backup clients 320.

The routine 700 can include fewer, more, or different blocks than thoseillustrated in FIG. 7 without departing from the spirit and scope of thedescription. Moreover, it will be appreciated by those skilled in theart and others that some or all of the functions described in thisdisclosure may be embodied in software executed by one or moreprocessors of the disclosed components and mobile communication devices.The software may be persistently stored in any type of non-volatilestorage.

Storage operations compatible with embodiments described herein will nowbe described. For example, data can be stored in primary storage as aprimary copy or in secondary storage as various types of secondarycopies including, as a backup copy, a snapshot copy, a hierarchicalstorage management copy (“HSM”), an archive copy, and other types ofcopies. Certain embodiments described herein with respect to backupoperations are similarly compatible with each of these types ofoperations.

A primary copy of data according to some embodiments is a productioncopy or other “live” version of the data which is used by a softwareapplication and is generally in the native format of that application.Such primary copy data is typically intended for short term retention(e.g., several hours or days) before some or all of the data is storedas one or more secondary copies, such as, for example, to prevent lossof data in the event a problem occurred with the data stored in primarystorage.

Secondary copies can include point-in-time data and are typicallyintended for long-term retention (e.g., weeks, months or years) beforesome or all of the data is moved to other storage or is discarded.Secondary copies may be indexed so users can browse and restore the dataat another point in time. After certain primary copy data is backed up,a pointer or other location indicia such as a stub may be placed in theprimary copy to indicate the current location of that data.

One type of secondary copy is a backup copy. A backup copy in someembodiments is a copy of production data and, in some embodiments, canbe stored in a backup format, e.g., as opposed to a native applicationformat. For example, a backup copy may be stored in a backup format thatfacilitates compression and/or efficient long-term storage. Backupcopies generally have relatively long retention periods and may bestored on media with slower retrieval times than other types ofsecondary copies and media. In some cases, backup copies may be storedat on offsite location.

Another form of secondary copy is a snapshot copy. From an end-userviewpoint, in some embodiments, a snapshot may be thought of as aninstant image of the primary copy data at a given point in time. Asnapshot generally captures the directory structure of a primary copyvolume at a particular moment in time and may also preserve fileattributes and contents. In some embodiments, a snapshot may exist as avirtual file system, parallel to the actual file system. Users typicallygain read-only access to the record of files and directories of thesnapshot. By electing to restore primary copy data from a snapshot takenat a given point in time, users may also return the current file systemto the state of the file system that existed when the snapshot wastaken.

A snapshot in some cases is created substantially instantly, using aminimum amount of file space, but may still function as a conventionalfile system backup. Some types of snapshots do not actually createanother physical copy of all the data, but may simply create pointersthat are able to map files and directories to specific disk blocks.

In some embodiments, once a snapshot has been taken, subsequent changesto the file system typically do not overwrite the blocks in use at thetime of the snapshot. Therefore, the initial snapshot may use only asmall amount of disk space needed to record a mapping or other datastructure representing or otherwise tracking the blocks that correspondto the current state of the file system. Additional disk space isusually required only when files and directories are actually modifiedlater. Furthermore, when files are modified, typically only the pointerswhich map to blocks are copied, not the blocks themselves. In someembodiments, for example in the case of copy-on-write snapshots, when ablock changes in primary storage, the block is copied to secondarystorage before the block is overwritten in primary storage. The snapshotmapping of file system data is also updated to reflect the changedblock(s) at that particular point in time.

An HSM copy can be a copy of the primary copy data but typicallyincludes only a subset of the primary copy data that meets a certaincriteria and is usually stored in a format other than the nativeapplication format. For example, an HSM copy may include data from theprimary copy that is larger than a given size threshold or older than agiven age threshold and that is stored in a backup format. Often, HSMdata is removed from the primary copy, and a stub is stored in theprimary copy to indicate the new location of the HSM data. When a userrequests access to the HSM data that has been removed or migrated,systems use the stub to locate the data and often make recovery of thedata appear transparent, even though the HSM data may be stored at alocation different from the remaining primary copy data.

An archive copy according to some embodiments is generally similar to anHSM copy. However, the data satisfying criteria for removal from theprimary copy is generally completely removed with no stub left in theprimary copy to indicate the new location (i.e., where the archive copydata has been moved to). Archive copies of data are sometimes stored ina backup format or other non-native application format. In addition,archive copies are generally retained for very long periods of time(e.g., years) and, in some cases, are never deleted. In certainembodiments, such archive copies may be made and kept for extendedperiods in order to meet compliance regulations or for other permanentstorage applications.

In some embodiments, application data over its lifetime moves from moreexpensive quick access storage to less expensive slower access storage.This process of moving data through these various tiers of storage issometimes referred to as information lifecycle management (“ILM”). Thisis the process by which data is “aged” from forms of primary storagewith faster access/restore times down through less expensive secondarystorage with slower access/restore times. For example, such aging mayoccur as data becomes less important or mission critical over time.

Similar data transfers associated with location-specific criteria areperformed when restoring data from secondary storage to primary storage.For example, to restore data a user or system process generally mustspecify a particular secondary storage device, piece of media, orarchive file. Thus, the precision with which conventional storagemanagement systems perform storage operations on electronic data isgenerally limited by the ability to define or specify storage operationsbased on data location.

Terminology

Conditional language, such as, among others, “can,” “could,” “might,” or“may,” unless specifically stated otherwise, or otherwise understoodwithin the context as used, is generally intended to convey that certainembodiments include, while other embodiments do not include, certainfeatures, elements and/or steps. Thus, such conditional language is notgenerally intended to imply that features, elements and/or steps are inany way required for one or more embodiments or that one or moreembodiments necessarily include logic for deciding, with or without userinput or prompting, whether these features, elements and/or steps areincluded or are to be performed in any particular embodiment.

Depending on the embodiment, certain acts, events, or functions of anyof the algorithms described herein can be performed in a differentsequence, can be added, merged, or left out all together (e.g., not alldescribed acts or events are necessary for the practice of thealgorithms). Moreover, in certain embodiments, acts or events can beperformed concurrently, e.g., through multi-threaded processing,interrupt processing, or multiple processors or processor cores or onother parallel architectures, rather than sequentially.

Systems and modules described herein may comprise software, firmware,hardware, or any combination(s) of software, firmware, or hardwaresuitable for the purposes described herein. Software and other modulesmay reside on servers, workstations, personal computers, computerizedtablets, PDAs, and other devices suitable for the purposes describedherein. Software and other modules may be accessible via local memory,via a network, via a browser, or via other means suitable for thepurposes described herein. Data structures described herein may comprisecomputer files, variables, programming arrays, programming structures,or any electronic information storage schemes or methods, or anycombinations thereof, suitable for the purposes described herein. Userinterface elements described herein may comprise elements from graphicaluser interfaces, command line interfaces, and other suitable interfaces.

Further, the processing of the various components of the illustratedsystems can be distributed across multiple machines, networks, and othercomputing resources. In addition, two or more components of a system canbe combined into fewer components. Various components of the illustratedsystems can be implemented in one or more virtual machines, rather thanin dedicated computer hardware systems. Likewise, the data repositoriesshown can represent physical and/or logical data storage, including, forexample, storage area networks or other distributed storage systems.Moreover, in some embodiments the connections between the componentsshown represent possible paths of data flow, rather than actualconnections between hardware. While some examples of possibleconnections are shown, any of the subset of the components shown cancommunicate with any other subset of components in variousimplementations.

Embodiments are also described above with reference to flow chartillustrations and/or block diagrams of methods, apparatus (systems) andcomputer program products. Each block of the flow chart illustrationsand/or block diagrams, and combinations of blocks in the flow chartillustrations and/or block diagrams, may be implemented by computerprogram instructions. Such instructions may be provided to a processorof a general purpose computer, special purpose computer, or otherprogrammable data processing apparatus to produce a machine, such thatthe instructions, which execute via the processor of the computer orother programmable data processing apparatus, create means forimplementing the acts specified in the flow chart and/or block diagramblock or blocks.

These computer program instructions may also be stored in acomputer-readable memory that can direct a computer or otherprogrammable data processing apparatus to operate in a particularmanner, such that the instructions stored in the computer-readablememory produce an article of manufacture including instruction meanswhich implement the acts specified in the flow chart and/or blockdiagram block or blocks. The computer program instructions may also beloaded onto a computer or other programmable data processing apparatusto cause a series of operations to be performed on the computer or otherprogrammable apparatus to produce a computer implemented process suchthat the instructions which execute on the computer or otherprogrammable apparatus provide steps for implementing the acts specifiedin the flow chart and/or block diagram block or blocks.

While certain embodiments have been described, these embodiments havebeen presented by way of example only, and are not intended to limit thescope of the disclosure. Indeed, the novel methods and systems describedherein may be embodied in a variety of other forms; furthermore, variousomissions, substitutions and changes in the form of the describedmethods and systems may be made without departing from the spirit of thedisclosure. The accompanying claims and their equivalents are intendedto cover such forms or modifications as would fall within the scope andspirit of the disclosure.

What is claimed is:
 1. A method of creating secondary copies of dataassociated with user computing devices in a shared storage pool,comprising: in response to instructions to create a secondary copy offirst data stored in primary storage associated with a first computingdevice in a networked pool of computing devices, accessing a datastructure associated with the first computing device that identifies afirst subset of computing devices in the pool that are designated forsharing storage resources with the first computing device; instructing,by a storage manager module executing in one or more processors, thefirst computing device to transmit the first data to a media agentassociated with at least one computing device in the pool and whichcreates the secondary copy of the first data in storage resourcesassociated with a second computing device in the pool that is includedin the first subset; in response to instructions to create a secondarycopy of second data stored in primary storage associated with a thirdcomputing device in the pool, accessing a data structure associated withthe third computing device that identifies a second subset of computingdevices in the pool that are designated for sharing storage resourceswith the third computing device, the second subset including the firstcomputing device; and instructing, by the storage manager module, thethird computing device to transmit the second data to a media agentassociated with at least one computing device in the pool and whichcreates the secondary copy of the second data in storage resourcesassociated with the first computing device.
 2. The method of claim 1,further comprising electronically distributing common data protectionsoftware to the plurality of computing devices for installation thereon,the common data protection software configured to manage the creation ofthe secondary copies.
 3. The method of claim 1, wherein the common dataprotection software comprises a data agent and a media agent.
 4. Themethod of claim 1, wherein the computing devices in the pool are incommunication with one another over a wide area network.
 5. The methodof claim 4, wherein the computing devices in the pool are incommunication with one another over the Internet.
 6. The method of claim1, further comprising, prior to said instructing the first computingdevice to transmit the first data: determining an availability of thestorage resources associated with the computing devices in the firstsubset; and based at least in part on the determined availability,deciding to create the secondary copy of the first data in the storageresources associated with the second computing device.
 7. The method ofclaim 1, further comprising determining whether the first computingdevice is available for use in restoring the secondary copy of thesecond data.
 8. The method of claim 7, further comprising compiling areport including an entry indicating the determined availability of thefirst computing device.
 9. The method of claim 1 wherein neither of thefirst data or the second data are transmitted to the storage manager inperformance of the method.
 10. The method of claim 1, wherein the firstdata comprises production data generated by one or more softwareapplications executing on the first computing device and the second datacomprises production data generated by one or more software applicationsexecuting on the third computing device.
 11. A system for creatingsecondary copies of data associated with user computing devices in ashared storage pool, the system comprising: a first data structureassociated with a first computing device in a networked pool ofcomputing devices and listing a first subset of computing devices in thepool that are designated for sharing storage resources with the firstcomputing device, where a second computing device in the pool includedin the first subset; a second data structure associated with a thirdcomputing device in the pool and listing a second subset of computingdevices in the pool that are designated for sharing storage resourceswith the third computing device, the second subset including the firstcomputing device; one or more processors; and a storage manager moduleexecuting in the one or more processors and configured to: in responseto instructions to create a secondary copy of first data stored inprimary storage associated with the first computing device, access andreview the first data structure to identify the first subset ofcomputing devices in the pool; instruct the first computing device totransmit the first data to a media agent associated with at least onecomputing device in the pool which creates the secondary copy of thefirst data in storage resources associated with the second computingdevice; in response to instructions to create a secondary copy of seconddata stored in primary storage associated with the third computingdevice, access and review the second data structure to identify thesecond subset of computing devices in the pool; and instruct the thirdcomputing device to transmit the second data to a media agent associatedwith at least one computing device in the pool which creates thesecondary copy of the second data in storage resources associated withthe first computing device.
 12. The system of claim 11, wherein thestorage manager is further configured to electronically distributecommon data protection software to the plurality of computing devicesfor installation thereon, the common software configured to manage thecreation of the secondary copies.
 13. The system of claim 11, whereinthe common data protection software comprises a data agent and a mediaagent.
 14. The system of claim 11, wherein the computing devices in thepool are in communication with one another over a wide area network. 15.The method of claim 14, wherein the computing devices in the pool are incommunication with one another over the Internet.
 16. The method ofclaim 11, wherein the storage manager is further configured to, prior toinstructing the first computing device to transmit the first data:determine an availability of the storage resources associated with thecomputing devices in the first subset; and based at least in part on thedetermined availability, decide to create the secondary copy of thefirst data in the storage resources associated with the second computingdevice.
 17. The system of claim 11, wherein the storage manager isfurther configured to determine whether the first computing device isavailable for use in restoring the secondary copy of the second data.18. The system of claim 17, wherein the storage manager is furtherconfigured to compile a report including an entry indicating thedetermined availability of the first computing device.
 19. The system ofclaim 11, wherein neither of the first data or the second data aretransmitted to the storage manager.
 20. The system of claim 11, whereinthe first data comprises production data generated by one or moresoftware applications executing on the first computing device and thesecond data comprises production data generated by one or more softwareapplications executing on the third computing device.